The Stovebolt Site Forums The Shop Area The HiPo Shop 383 "New build" smoking

I built a 383 for my 3600 from a 1991 350 TBI and it runs well, pulls strong, etc. and it has about 400 miles on it so far. The block was machined 0.030 oversize and honed by a machine shop that I trust but don't have any personal experience with.

The problem is that when driving to car shows and similar when I arrive and putter around the parking area to get to my parking space it smokes noticably, I believe from both exhaust sides (independent dual exhaust). Oil is 5W30 and it used about a quart in between the first oil change (roughly 100 miles) and the next 200 miles. Typical drive to the shows is 40-45 miles, mostly at 55-60 mph with no noticable smoke when driving or initial operation in town after highway driving at 25-30 mph. Engine speed at 60 mph is approx 2200 rpm.

I suspect that I don't have the rings/bores suitably broken in but wondering about all sorts of other potential issues. I have tried to do high load pulls like 4th gear from 30 to 60 mph (roughly 3000 rpm) to help seat the rings but I'm not sure that is working.

It has been a few years since the engine was assembled and I am now questioning what I did for valve stem seals (memory is a terrible thing to loose).

My PCV system has the valve mounted in the passenger side valve cover connected to the base of the carburetor - connected to the intake manifold vacuum with the "clean air" supplied from the clean air side of the air filter to the driver's side valve cover. I don't recall what variation of PCV valve I have.

Any advice about what to investigate or was to get the rings seated would be appreciated.

If this should be in the engine forum please feel free to move but as a non-standard engine I assumed it should go in the HP forum.

First thing to check is the PCV hose, does it have oil in it? A simple test is to install a clear 3/8" inline fuel filter in the PCV line then go drive it. If it's sucking oil the filter will have a bunch in it.

Next is pull the valve covers and see if you can see the valve seals, its pretty hard to see them but you want to make sure they are still installed correctly. You may need to fill a cylinder with cotton rope and pull the valve springs to check. I worked on a Pontiac that sat before starting, all 16 seals were riding up and down with the valves, they installed cheap seals that didn't fit the head and after it sat they dried out.

Thanks Joe. The PCV test should be pretty easy as a starting point.

If I need to pull the valve springs and check/replace the stem seals I may wait until winter. The engine did sit for at least 2 maybe 3 years between assembly and first firing, and almost a year after that before it got any real operation due to the remaining activities associated with my build.

Under the valve cover do you have a baffle where the PCV goes?

To use that much oil that quickly, the valve guides would have to be sloppy loose- - - - -even bad stem seals won't cause that rate of oil loss. I diagnosed one failed rebuild that was using oil about that badly- - - - - -it turned out that the rebuilder had forgotten to install the oil ring on one piston. That guy got a pretty bad case of Budweiser Fever on a regular basis! Another one (my own fault) was a re-ring job on a Rambler American flathead six that completely wore out the rings on a 2500 mile trip from California to Tennessee. By the time we arrived in Nashville, it was using 3 quarts of oil to a tank of gas. I hadn't cleaned up the cylinders properly after honing them, and the hone grit imbedded in the cylinder wall pores wore out the rings. The oil ring expanders were rubbing the cylinder walls, and the compression rings were less than half their original thickness. I'd recommend a complete teardown and inspection of the piston ring installation.
Jerry

I join with Jerry on the valve guide idea as the main problem.

Also there could be a secondary problem...Did you use chrome piston rings? About 50 years ago I used the last of those I will ever put in any engine. You can see an image below showing the hatch marks are still visible. The engine had over 25,000 miles on it when I removed it. The rings never did break in correctly. Just another thought.

There are baffles in the valve covers for the PCV connections.

I need to check back on what rings I used, I don't recall them being chrome but my memory is not the best on the details.

I am pretty sure the valve guides are not sloppy loose but again it has been a while since it was put together.

I'm not anxious to pull the engine and tear it down but if I need to do that it will be a winter project.

WICruiser, I built a 355 years ago and put in a big block oil pump only to help smooth the pump and distributor, the big block pumps have larger gears with more teeth and run smoother. I ended up pulling that pump out and installing a stock small block oil pump, no high pressure or high volume. Oiling troubling was solved with the stock pump. Just wondering if your 383 has a high volume and/or high pressure pump?

78buckshot, as I recall I installed a high volume but not high pressure pump reasoning that more oil was a good thing (maybe too much isn't).

Oil pressure is about 60 psi cold, 45 psi warm at 2200 rpm, 30 psi warm at idle.

Coolant is running at 185 or so with the fan on full time (I have a thermo switch issue so bypassed for now). Temperature comes up normally to the thermostat opening temperature (I bleive it is a 195 if I recall correctly). Before bypassing the thermo switch I did have temperatures as high as 220 when vehicle speed was low that came down with increased vehicle speed.

Those numbers are pretty close to stock, probably not causing the problem. If you happen to pull the oil pan and have a stock pump on hand, it might help to use it. From your original description, my bet is a piston/cylinder/ring seal issue.

I am slowing, grudgingly coming to the conclusion that the problem is ring/bore sealing and while it's possible that the rings will still break-in my confidence is not very high.

The engine was built using a Scat rotating assembly kit that included pistons and piston rings that were described as having "Plasmamoly" facing material.

Thanks for all of the input received to date. I have a list of things to evaluate and continue to hope that I do not need to pull the engine for a tear down this winter season.

Perform a cylinder leak down test, that should give you a little more info to chew on.

Unless you're running extremely loose oil clearances on all the bearings, the only thing a high volume oil pump does is puts a lot of unnecessary stress on the distributor drive gear. On the race engines we ran .0025-.003" bearing clearance to allow the engine to rev up quickly, so a high volume pump was necessary just to maintain normal hot engine oil pressure. Doing race stuff on a street engine is usually a foolish thing to do. We built those engines to produce lots of power for a very short time. A round track engine with 1K miles on it was an antique!
Jerry

HRL - thanks, I should have known that and agree with the idea that race stuff on street engines is stupid squared but I guess that puts me into that cast of characters.

I contacted Scat (the source of the pistons and rings) but all they could say is they need to know the piston to bore clearance and ring end gaps so until I tear it down thay are not going to be any help.

I have read elsewhere that there may be a leak from the valley into the intake past the manifold gaskets. I'm running the original cast iron TBI heads with an Edelbrock Performer EDL-2104 intake manifold. I plan to check/re-torque the intake manifld bolts but is there anything else I should be doing/checking to confirm or eliminate this potential leak path?

This.......

You stated that it runs real well, if you have a significant leak on the underside of an intake gasket, I think you would notice low vacuum and poor running. You could pull the spark plugs and keep them in order, then compare plugs with each other. If one or more plugs looks oil fouled, you may have a leak but not very probable.

I am waiting on a leak down tester but looked at the PCV valve (no excessive oil in the hose), a few spark plugs (all were similar with one light and one dark side of the center porceline, no evidence of oil), and attempted to look at the valve stem seals (valve springs prevent viewing them). I did confirm that there was no obvious oil smoke on start-up after sitting for several days compared to significant oil smoke at idle after driving.

Once I have the leak down test information I may be better informed but I am leaning heavily toward running it for the rest of the summer to see if anything changes and if not plan to tear it down over the winter months. Other than the anoyance factor of being a smoky truck when driving into car shows and needing to add oil more often than desired there doesn't appear to be any significant risk of additional damage to anything.

I also confirmed that the oil pump is standard volume and pressure so my memory was wrong but my selection was okay.

You won`t be any fan of somebody behind you whilst driving.
Most likely a burnt/warped ring. Running too hot or w/o enough oil. But I think you`d notice power loss.

No visible smoke when driving except at slow speeds after driving at highway speeds and no apparent power loss. Engine is operating at normal coolant temperatures and oil level is in the safe range.

I agree that people behind me when driving at slow speeds will not be my fans so I will try to limit that situation but car shows tend to require a fair amount of such driving between the entry point and the eventual parking spot.

I should have leak down results in a week or so and probably will determine how best to hold an intake valve in place so I can remove one valve spring and get a good visual of the stem seal. I am pretty sure I can find a tool to compress the valve spring with the head in place (my normal spring compressor requires the head to be loose). If the problem is stem seals I can probably remidy that with the engine in place but just about anything else will require engine removal and tear down.

Its smoking when you are going fast, you just don`t see it as well. with my 327`s and the price of oil.
I solve every oil leak I can. I have it down to one very minor leak with the mechanical fuel pump. Just a drop or 2.
Dang quart of oil is up there.

Here's the tool you'll need for "head installed" valve spring removal:

www.ebay.com/itm/127446696906?

Either rig an air pressure adapter from an old spark plug shell and a quick connect air hose fitting to hold the valves closed with a manual transmission in high gear, or use two pairs of vise grips on the flex plate of an automatic trans, or pack the cylinder full of 1/4" nylon rope (20 feet or so) and turn the piston up against it. Be VERY careful not to drop a valve into a cylinder, or you'll definitely be pulling a head!
Jerry

I agree that it is probably burning oil when I am not seeing significant smoke but even at today's oil prices it is cheap compared to all the gaskets, rings, etc. required to rehone the cylinders (not that I won't do it over the winter).

I purchased a cheap leak down tester and after I was able to get it working (I think) I measured leak down at 15-20% cold (I know hot is better but much harder for me to accomplish). Inlet pressure was only 28-29 psi for this tester so not the 50 or 100 psi I have seen referenced but don't know if that affects the results. The output gage is marked in percent leakdown with my readings in the green (okay) region.

The plugs vary a fair amount in color/deposits. I tried to take pictures from 2 opposite angles but its hard to see anything meaningful in them. Number 8 is very clean, almost too white whereas some of them show more significant deposits. Leakdown on #8 was no different than the others.

I plan to remove at least one of the intake valve springs to get a better picture of what I have for valve stem seals. I doubt that the stem seals are the majority of the issue but I want to refresh my memory about what I did when I assembled the heads. HRL thanks for the link to the tool required and the procedure to secure the valve.

Have you looked at a plain old vacuum gauge test and a compression test? Vacuum readings can reveal a lot...

Jon, I have not, but always good to have more information so I will add them to the list of things to test before developing a plan.

"Cylinder leakdown" is probably one of the most useful, yet misunderstood tests for engine diagnosis, and doing it right is extremely simple. All you need is an air compressor capable of developing 100 PSI, a pressure regulator with a gauge, and a way to apply the air pressure to the cylinder. The same quick connect adapter used to hold the valves closed while changing valve seals also works for a leakdown test. With a manual transmission vehicle, just put the transmission in high gear, chock the wheels front and rear, and pressurize the cylinder with both valves closed. The simplest way to do that is to loosen both rocker arm adjusters so both valves are closed with the piston close to the top of its travel on the compression stroke- - - - -not necessarily right at top dead center. Adjust the air pressure to 100 PSI with no air flowing, plug the air line onto the cylinder, and look at the pressure gauge. For instance, an 85 PSI reading would be an 15% leak rate. A recently rebuilt engine should test in the mid to high 90% range. Below 80% is a disaster. Listen for intake valve leaks at the carburetor, exhaust valve leaks at the tailpipe, and piston ring leaks at the oil fill cap. It's not "rocket surgery"!
Jerry

At this point, you already know its leaking past the rings or the valve seals. There is no reason to keep checking it. You either keep driving and watching the oil level or you pull it and fix it. If you used a flexible sealer when assembling the engine, most of the time they come back apart pretty easy and you can get away with just a few new gaskets. I would recuse the head gaskets if they come off clean.

I don't remember if you said what cam and lifters you have, so choose your oil wisely. If I was spending $10 or so per quart of good zinc oil, pulling it now would be my choice. I couldn't stand not knowing what's wrong.

I refreshed my '85 Dodge 318 over a weekend, it was my only transportation, so I did a fast clean up and used fairly cheap parts, no machine work. The rings never seated in the freshly honed cylinders, it was using 3 quarts of oil everyday. The next weekend it came back out for a ring change. It came apart easy, I replaced the rings with a better set. I got it back together for work on Monday and the oil usage was gone, it ran another 80,000 miles before I sold it off. Compression before the refresh was so low, the leak down test would spin the engine like a starter, it only took one cylinder test to know it was worn out.

I am leaning toward pulling it because I want to know what I did wrong the first time. I agree it should come apart fairly easily, and hopefully it will become obvious what is wrong once I pull it apart.

I used the COMP Cams SK12-242-2 cam and lifter kit when it was built, so all new but flat tappet.

I have been using Vavoline 5W30 oil that says its a synthetic blend (can't seem to find any oils that are not partially synthetic) and I suspect that is not helping the ring seating process. I added a ZDDP additive to the initial fill and again at the first oil change (rooughly 100 miles) to try and protect the flat tappet cam.

I am assuming that I will need to tear it down completely, flex hone the cylinders to break up any glazing, wash everything and reassemble. If I put the lifter back into the same locations they should be fine. New piston rings and some gaskets.

Thankfully time is not really a factor as the only thing having it sitting prevents is attending some car shows that I go to just to participate (didn't build it as a show truck).

I'll second Joe's comments. Back in my poor boy, broke days I reused many a head gasket. If they looked good, I'd wipe em clean with gasoline, and spray a heavy coat of aluminum spray can paint on both sides, while it was wet slap the heads back on. Never had a failure. A couple times I did this cheap....uh, frugal method on some pretty good running 10.5 340 engines.

Another poor boy trick that never failed was instead of boring and honing, which is always best, I'd knock the ring ridge out of the cylinder and hand sand with my best cross hatch twist using dry 180 grit.

On piston rings, the cheapest were often chrome rings. Against all common wisdom and advice I installed them dry, no lube in the cylinders. They seated (broke in as we used to say) instantly, no smoke or oil use. Never had a problem like broke rings or early oil use from cylinder scarring. As a old friend liked to say, sometimes better to be lucky than smart.

RonR

this oil for break in

The rings won't seat with 5w30 synthetic blend. Change it and put the 30w in with the zinc additive. Then go out and floorboard it from 30 to 60 in high gear, then coast back down to 30, repeating this process at least ten times. That's how I've broken in every engine I've ever rebuilt, and not one ever used any oil. Either moly or cast rings.

Tronman, do you think the process will still work now that the engine has about 500 miles on it, or will the bores be glazed too much?

Guitplayer - where would I get the break-in oil you suggested?

Summit racing sells the Penn-Grade oil, the break-in is 30w and really works good. You are correct on the cam and lifters, do what ever you have to do to keep them in the same location, you should be good on break-in after 500 miles, so go with a 10-30 Penn Grade oil, no more mixing additives. A rougher hone and different rings should get you back on the road.

summit or amazon wicruiser

If you have to take it apart and start again be sure (really certain) the clearance between piston and cylinder is spot-on correct and also that the cylinders are round with no taper. I'm not a fan of break-in oil. As long as you're using an oil that's good for a flat tappet camshaft (like VR-1 30 weight for example) I feel you'll be fine. I know some folks are real fans of this or that oil...and that's fine but I'm just not in that crowd. And get it honed properly for the rings you'll be using. All this is important. I expect you've got some glazing now. As somebody else said get away from any synthetic oil. Good luck!

Thanks Jon, I understand your comments about oil preferences.

I am still hoping (maybe unrealistically) that I can save it without taking it apart. If I do take it apart, piston to bore clearance is one of the many things I plan to document (kicking myself for not doing it originally).

If you can give us the results of a vacuum test at idle, I think there'll be some good clues there. A leak-down test will be good also, but I think a plain old vacuum gauge reading is easier for most folks. A leak-down test will not show bad valve guides whereas a good vacuum gauge probably will. If you have a liquid filled vacuum gauge it will dampen the bounce effect of the needle at idle (which if it happens will negate any sort of idle vacuum accuracy). If you have a non-liquid filled gauge and the needle at idle is bouncing back and forth like crazy, try pinching the hose. That will normally cause you to get a more realistic reading. Back when these gauges were more universally popular (hence engineered better and made in the USA) most of them included a restriction but the ones I see today (from a country with five letters, beginning with the letters Chi which is not Chile) just ignored that kind of thought. I attached an image of the connection spot for a Helicoid brand gauge so you can see. Hope it is helpful.

.

Good luck!! I hope you get it figured out.

Not know much about SBC's, could this be different block with harder cylinders? Seems to me I have read somewhere the material is different which makes the cylinders harder for longer life, this could explain the rings not seating if the walls are not honed correctly.

I'm betting it won't seal up, after 500+ miles, it should have by now. I have never used synthetic oil or blends for break-in, its been said its too slick for the rings to seat. But you can't just throw in any oil due to the flat tappet cam, so ask the ring manufacturer what they recommend.

Good luck,

I measured intake vacuum at 15" but given the overlap in the cam I am not sure the low reading is an indication of a problem. The engine was cold and idle was not smooth so I probably need to retest it to be sure of the reading. My vacuum gage is older and seemed stable but I didn't check it for an orifice.

The block is a 1991 Chevy 350 that was machined oversize and honed by a machine shop that has a good reputation.

Consensus seems to be that at this point the rings are not going to seal any better so I will probably run it a bit more before scheduling a time to pull the engine and tear it down.

In the past I have always used standard (not synthetic) oil and not had a break-in problem but this time I struggled to find an oil that was not a synthetic blend (probably didn't look hard enough). Engine oils are constantly changing formulations and seem to be trying to get longer and longer service intervals which is great except for break-in.

Lots of problem engines have been fixed with a slurry of Bon Ami and Marvel Mystery Oil- - - - -

www.ebay.com/itm/127479100239?

Jerry

GM used several different alloy blends for cast iron blocks, some with higher nickel content, some with higher tin content. The mid-seventies block I used to build a 383 has 10% nickel for a longer lasting bore and 10% tin for better control of expansion and contraction. The break-in procedure and type of oil is the same for all of them.

HRL - I am not sure how the "slurry of Bon Ami and Marvel Mystery Oil..." would be utilized? I do appreciate the information but just need a little more insight to be able to use it.

The grit in the abrasive cleaner will help break any glaze and provide some friction for the rings to scuff the cylinder walls.

The ad copy for Bon Ami and the logo on the package showed a newly-hatched baby chick, and the slogan "Hasn't Scratched Yet!" I believe the very mild abrasive material they used was the secret to "ring seating" on glazed cylinder walls by mixing 2-3 tablespoons of Bon Ami with half a pint of lightweight oil such as MMO or even Diesel fuel, and dribbling the slurry down the carburetor of a warmed-up engine running at fast idle. The idea was to create a little scrubbing action by the piston rings to help stubborn rings seat. Some mechanics in the 1950s swore by the procedure- - - - -others swore at it! As always, "Your results may vary!" Just thought I'd pass on a little old geezer trivia to the collective!
Jerry

The real question is, would you ever use it in one of your engines, Jerry?

And I know that you have the ability and equipment to completely tear down and rebuild an engine but let's assume for the sake of argument that you did not have that access or ability at this time. Would you try the bonami solution?

I have used that process on occasion, with mixed results. One oil-burner engine we tried to rescue after a botched rebuild by a different shop didn't work, but we found out later that one piston was missing an oil ring. Other times, the oil consumption got reduced pretty dramatically and we didn't have to open the engines up and redo the ring job. Even if the engine might need a rework later, the Bon Ami won't do any further damage.
Jerry

HRL, thanks for the details about the procedure. I was concerned that the Bon Ami was mixed with the engine oil and the affect that would have on all the bearings. Dribbling into the intake makes sense and if everything else fails I may give it a try as a last resort prior to pulling the engine for tear down.

My valve spring compressor is scheduled to be delivered today and I plan to inspect the valve stem seals on cylinder #1 to see if they offer any clues.

Follow up with a heavy dose of straight Diesel fuel trickled down the carb to flush away any residue so the polishing action doesn't get overdone. A beneficial side effect will be a drastic reduction in the local mosquito population from the cloud of exhaust smoke you'll create.
Jerry

The break in procedure I mentioned earlier will either work or not, but at least it can't hurt anything and costs only some fuel to try. I still think some plain ole' 30w non-synthetic will help.

Troman, thanks for the input. Your procedure is definitely on the list of things to try prior to pulling the engine.

No problem, I sure hope it (and/or some combination of the other procedures mentioned) reduces your oil usage enough that you may must run it.

Just to confrim what I did when I built the engine I remvoed the valve springs on both valves for cylidner #1 (used the rope method to hold valves).

Valve stem seals look as I would have expected so moving on to other action items on my list.

Well those look pretty good. Dang it! Would have been easy if you'd found this to be your problem. Looking at your spark plugs, #1 and #7 seem to have the most crud. So maybe check the seals in #7 as the others look fine.

I was now years old when I first learned of the Bon Ami procedure here in this forum, although my Dad and I did glaze break the cylinder in a lawn mower with Ajax cleanser, but that was pretty easy to get the head off and back on again! We just wiped the cylinder with it and then spun the crank.

I notice in your photo that you're not using the O rings on the top of the valve stems, along with the positive seals. That's a good thing, as it's possible to "over-seal" the guides and wear them out for lack of lubrication. I've seen that happen on several engines. Use one or the other- - - - -not both. I like to use the positive seals on the intakes only, as the exhausts do not have intake vacuum against the bottom of the guides. O rings only on the exhausts are plenty of sealing as long as the sheet metal deflectors are used over the valve springs.
Jerry

I installed 30W break-in oil with a ZDDP additive yesterday and proceeded to run several cycles of WOT acceleration from 30 to 65-70 in 4th gear (1:1 ratio) coasting back down to 30 with the carburetor at idle. Engine speed at 65-70 is in the 3500 rpm range (just a quick glance at the tach as watching the road pretty cloase at those speeds).

It will be a while before I have enough miles on it to know if things changed or remain the same and will report back then.

Awesome! A dozen of those and some other driving will tell if it helped or not. Sounds like it does run good, tho. If the oil consumption isn't too severe and you're not daily driving it, maybe just throw a quart of oil in once in awhile and send it :-)

Short update, I have put about 70 miles on since the "break-in" procedure and oil smoke seems to be reduced but not gone entirely. Oil consumption also appears to be less but not zero. My current plan is to run another "break-in" sequence and put on some more miles before taking any other significant actions.

Great news! I just checked your Project posts and see you've got a Really nice truck. Shame it's not set up with a bumper that'd allow a few thousand lbs of trailer and load to hook up. A few miles (or hundred) miles of work would probably bring the engine around a bit quicker.

Thanks for the compliment.

I have considered adding a hitch (frame mounted) but decided that would lead down another rabbit hole for wiring, brake controller, etc. that I don't want to pursue.

I am planning to put some more high load acceleration loads on the engine to help bring it around.

A truck without a hitch is like a day without sunshine, don't let the wiring scare you, we can all help you with it. Glad to hear the engine is improving.

I'm not scared of the wiring as much as I am the inclusion of a hitch leading me to consider my '50 as a replacement for my 2024 Ram that I currently use for any towing. I know it would lead to my using the '50 more as a truck and daily driver but while that could be a good thing it does have it's limitations.

I would love to use my '57 more often and even as a daily but the fuel milage is a big draw-back. The truck weighs about 7200 lbs, and with the 6.80:1/8.20:1 gears it keeps the 283 spinning at 2800 - 3500 rpm when on the road. I haven't actually clocked the mpg but estimate 6-7 mpg based on driving. It could tow with no problem if needed. My daily driver is a 2011 Chevrolet 2500HD, 6.0 gas, 4x4, 8 ft. bed full crew cab. The 4.10 gears make it a gas hog also. If I want to conserve fuel and can do an errand on the Harley, I take it.

I've been saving gas by doing errands on one of the electric cargo bicycles that I sell. It can haul 440lbs (rider and cargo) though I've never put that much on it. Such a long wheelbase, it almost rides like a Harley!

The 51 GMC 3 ton with a 12 foot flat bed that I'm about to "restore" is going to have a gooseneck hitch and a square tube hitch receiver. It's got a 270, a SM 420, and a 2 speed vacuum shift rear axle, and part of the resto-mod is going to include a 3 speed Brownie transmission. That's 24 forward speeds and 6 in reverse- - - - -which should be adequate to tow anything I can load onto a trailer!
Jerry

Say, Jerry, can you pass on what model Brownie it is, as I’m looking
for the same for my ‘54 GMC 450 firetruck conversion.

I'll need to take a couple of pictures of the data plates. I have two- - - -a big one that I'm intending to install in my 61 American LaFrance fire truck with the 401 GMC V6 and a direct drive Clark 5 speed, and a smaller one for the 51 GMC flat bed.
Jerry

Just a quick update - drove to another car show last weekend. It was closer than the previous ones but I did note less (but not no) smoke after idling in line to enter. Oil consumption appears to be reduced although not really enough miles yet to say for certain.

Given what I now know I think we can close this thread assuming that I will still be able to refer back to it in the future.

Good to hear.

Sounds like it's coming around. If you could work in a day trip of at least a 100 miles one way with as many hills as possible (Great River Rd ?) it might make for a nice finish to the story.

If not, well there's the drive. Never regretted a long cruise in any of my rigs.

Good Luck!

I have not managed to make a 100 mile one way trip yet but I did go to another show about 40 miles one way over the weekend. I noticed smoke once while driving accelerating out of a roundabout. Oil level has dropped but my perception is that the rate is lower. I am trying to incorporate different acceleration patterns to vary loads during driving to see if that helps over time.

If rings aren't properly seated during initial break in run it might continue having oil consumption issues in my experience .

Thanks BC59, I understand that is a potential but I am trying/hoping for an outcome that will not require me to remove the engine to deglaze the bores. At this point the only problem with procrastination is consuming some oil and with the minimal miles driven it's not too bad a compromise.

Just a quick update.

Given that the oil consumption remained higher than desired and I have observed some occasional smoking exhaust I decided to try the BonAmi treatment.

I drippled a few tablespoons of BonAmi mixed into diesel fuel into the carburetor while running the engine at a few thousand rpms. Then I ran another break-in sequence of WOT accelerations in 4th gear with coast downs in between. Then I changed the oil and oil filter to a conventional 30W oil.

I'm not sure how many miles I will get on the truck before the snow flies but hopefully enough to know if I need to pull the engine over the winter.

WICruiser, if you want to bring your truck across the pond to Michigan, I can drive it through the winter for you! That way it won't just sit around. I could do a bunch of cold starts and leave it sitting for extended periods of time idling, that should scuff the cylinders. Let me know if the offer appeals to you.

78buckshot, I was considering making it my daily driver and here they don't over salt the roads like they do in SE Michigan (I grew up there) but I have grown too comfortable with modern conveniences such as ABS and traction control (even 4WD) for our sloppy weather.

That being said I could do the cold start, extended idle here without spending the money required to drive to SE Michigan (gas is crazy expensive these days for 10 MPG vehicles).

I drove from Chelsea to Hubbard Lake, picked up our little travel trailer and then up to Mackinaw City, did the big truck show in St. Ignace and then back down to Chelsea with the trailer, cost me $300 in gas, I can't do that very often or my pension checks won't cover it! My daily/trailer puller is a Chevy 2500HD with the 6.0 gas, 4.10 gears, it is thirsty. I assumed the roads would require salt in your area. Where did you grow up in Michigan? My roots are in Ann Arbor.

Chelsea up to St. Ignace is a ways and with the speed limit up to what 75 now I suspect the fuel consumption is getting that much greater.

I grew up in the Walled Lake/West Bloomfield area.

Roads around here could use salt but the town roads generally just get sand on the hills and intersections, I guess its a cost thing. County and state roads get salt treatment, some even get brine treatment.