The Stovebolt Site Forums The Shop Area Engine Shop It works! It actually works!

Here's a short video of my 235 being started for the very first time. My first engine rebuild.



If you noticed the knocking before start-up, my oil pump's suction arm got slightly bent about a year ago. The crank just barely hits it on the upswing, so I'm gonna have to pull the pan and fix it. But, because it hits it on the upswing, once the engine actually fires, it just turns the threads and moves it out of the way. Very easy to fix, I just need to tighten the pipe up a bit.

Other than that, I've ran the engine for longer periods to test and everything seems to sound great. I haven't made timing adjustments or final valve adjustments yet, and it's on a straight pipe, but to my untrained ears it sounds like music!

Thanks for the help guys!

Congratulations

How did you get Brad Pitt to appear in your movie?

Congrats! I was smiling too - and not because you got Brad Pitt to start your engine!

Hope you're not running too long without coolant!

If you have not figured it out already, pull the starter lever back once the engine starts. It will be much quieter.

Haha, Brad Pitt my rear end! Maybe if I stop brewing beer and lose some of this beer weight, I'll be half-way there.



Thanks man! I made sure to shut it down real quick. I've worked on the engine so long without starting it that a cockroach came flying out of the water pump when I started it. Guess he had a bad morning.



It was actually sticking, so I put all the linkage on for that video. I think I'm gonna get a tighter spring so I don't have to worry about it anymore. I repaired the old foot starter instead of going with the solenoid so it's just a little worn.

Thanks guys!

If this engine has a new cam and lifters they need to have the proper break-in procedure.

congrats!

Oh no, what have I missed? I was just planning on running it at 2000-2500 RPM for 20-30 minutes with no idling and fluctuating the RPM.

I know you must be "pumped" now after hearing it run. Take care of the little things you mentioned and be sure to take Cletis' advice. Don't want to scew up now!!

Put a muffler on it before starting again, and break it in if its a new cam. Read up on break-in procedures if you are unsure of what to do. If this was a race engine with a radical cam, you could almost bet the farm the cam was bad already! It only takes a few minutes to round off a cam lobe or two. At least tell me you have a oil additive like EOS or Comp Cams Zinc additive in the oil.

Joe

It is a little late for a proper cam break in procedure. That needs to be commenced at the very first firing, not sometime down the road. These are water cooled engines by the way.
I just read a previous post, where you said you ran your battery down a few times cranking your engine trying to get it to start, that along with what you show in your video, is enough to make me think you have most likely lunched a cam. If you didn't you are very lucky.

Well, no one in this thread has told me what 'Proper Cam Break-In procedure" actually is, so I don't know if I did it or not.

I did what I was taught and told by family members. This isn't the first start-up by the way, this was just a video I made to show you guys.

I pre-oiled the system with a healthy amount of LUCAS Break-in added, because it has the zinc. I did this until it ran out of my rocker arms. I set my valve adjustments to the correct amount, with just the smallest amount of leeway for final adjustment since they are hydraulic lifters. Usually this involves them just being tight without having squished the hydraulic. The engine wouldn't start so obviously I had to turn it over a few times. Once it started, I varied the RPMS, never letting it get low. And seeing as it's quite obviously a water cooled engine, I did not run it for very long, no more than 5 seconds. I'll be running it for the full 20-30 minutes once it's hooked up correctly. This is an article that illustrates the procedure I followed: http://cranecams.com/uploads/breakin/548e.pdf

Every article I read on how to break in a cam only mentions that^ information. So what did I miss?

Cam break-in is the FIRST thing you do, immediately after the first startup, as soon as you see oil pressure. The first few minutes of running are critical, due to the scuffing action of the cam lobes against the bottoms of the lifters. The high RPM is needed to assure that lots of oil gets thrown off the crankshaft and rods to flood the cam with oil.

I've seen race cams with high valve spring tension ruined by less than a minute of idling on startup. We generally assemble the heads on our round track engines with street-type valve springs, do a cam run-in, then remove the heads and install the race springs. The cost of a couple of head gaskets and a few hours of labor is insignificant, compared to the possibility of ruining a $1,000.00 cam and lifters on a $15,000.00 engine.

Maybe you got lucky, but don't run it again until you can do the cam breakin right.
Jerry

VanattiWorkshop : nice video !
On your wooden engine test stand, have you got any detailed pics?
That stand sure seems to work better than I would have thought, and I would like to make one too!
{May I suggest a nearby fire extinguisher next time you test run the motor; I learned that necessity the hard way}

To the people mentioning breaking in a 235 cam; is that advise for some aftermarket cam, or a stock cam?
The reason I ask is that I can't seem to find any info in the Chevrolet Shop Manuals of the 1950's on stock cams needing additional break-ins.

Jerry: thanks, from what you said it sounds like I'm fine then. I ran it for about 5 seconds to verify oil pressure. I would have then mounted it and done the break-in procedure, but I heard a noise which ended up being that oil pump issue I mentioned. So I waited till the next morning and ran it another 5 seconds to make sure and to also get that video. It's mounted now, so as long as everything I mentioned up there^ for my breakin procedure is right, then it sounds like I'm fine. From what everyone was saying, it sounded like I was missing something in my procedure ...

Jack: Haha, sounds like a story worth hearing! I always have two fire extinguishers on either side of my garage. I built a mechanics pit into the floor (not easy in Florida, but so much cheaper than a lift!) so there's one in there too. My stand's design isn't the best, but I'll send you some pics when I get home. I'd have preferred to weld one together but metal isn't cheap near me unfortunately.

Cam break-in was something us hotrodders learned the hard way when we began using heavy-pressure valve springs to prevent valve float at high RPM. Back in the late 40's/early 50's it wasn't as big a problem because cam profiles and spring pressures weren't as radical. Recently, it's become more of an issue due to most oil refiners reducing or eliminating the zinc compounds in their motor oil that used to protect flat-tappet cam lobes. Today's roller cams don't stress the lobes nearly as much as the scuff action between a flat tappet and a cam lobe.

It might be OK not to run-in a stock stovebolt cam, but I'm not going to take that chance when the first 20 minutes or so of operatin can be done at 2K RPM and avoid the problem altogether. I also don't bet my life on bargain brake jobs, or draw to an inside straight. I'm not that much of a gambler!
Jerry

Yeah, as far as I've read it's only a problem on older flat-tappet cams. They took zinc out of motor oil for a variety of reasons, but the most well known is that it started ruining catalytic converters. But with flat tappet lifters, there is a point where the edge of the lifter slightly cuts into the lobe of the cam during initial break-in. This was largely prevented by the older zinc oil, so to rebuild older engines, you use zinc additive. That's just how I read it anyways.

To re-iterate, I had more than a pint of Lucas Break in (which is their zinc additive) in with my 10W-30 pre-primed in the engine, and I only ran it for a few seconds at a higher RPM, with the valves already adjusted and the timing mostly set (still have to fine tune once it's running) Now that it is mounted on my frame, I'll be hooking up all the bells and whistles and I will run it for 20-30 minutes at an RPM varied between 2500-3000. That's just how I was taught to break-in an engine by my Grandpa and Dad.

Is that wrong? All those guys saying I ruined my cam by not following correct procedure have me worried now.

Getting impatient to hear it run before it's ready to do the cam breakin has tripped up a lot of people. Chances are you haven't done any damage, but there's absolutely no excuse for taking foolish risks. After you've built a couple of hundred engines, you'll get over your youthful exuberance. If you manage to trash a few engines in the process by making immature mistakes, that's what Dave Ramsey, the financial advisor, calls "Stupid Tax". What really hurts is to watch a mega-dollar tractor pull engine hand grenade itself on the dyno while pulling 700+ horsepower at 6500 RPM. I did that a few years ago. It had a tiny vacuum leak that overheated one piston and melted it.
Jerry

Holy moly! I'd imagine that working on racing engines and high powered engines must have much tighter tolerances across the board that you have to watch out for. I'm glad I get to keep it simple.

I hope I'm not beating a dead horse, but I still can't figure out where I went wrong though.

I only ran it for 5 seconds to verify oil pressure and that it started, and then shut it down. During that period, it had break-in oil, was pre-primed, and already had the valves and timing pre-adjusted. Now that I know it starts, I'll hook it all up and do the 20 minute procedure. Do most guys actually hook everything up and run it for the 20-30 minutes on the very FIRST start? I'm nowhere near that confident in my abilities!

It's, like you said, my inexperience talking but I was convinced the thing wouldn't even start so I wasn't ready to mount it and hook it all up before I knew it actually ran. But if that's all that was done wrong, then I feel a bit better and won't make that mistake again. Being my first engine, I'm just glad it didn't explode.

yes the very first start, with hopefully no more that 2 or 3 revoulutions before it fires. And you only shut it down if you absolutely have to.Did you use the cam lube, the thick grease looking stuff? You never mentioned that. You said you ran the battery down 3 or 4 times in about 10 tries. All that cranking is what would worry me the most. You can have the best oil in the world all primed up as much as you want and will do the cam no good it only gets oil from the oil thrown from the crank and whatever else gets splashed around, there are no oil passages to the cam lobes.

I will add my 2 cents,

The first few revolutions, weather with starter, by hand, or running are the most important. The cam lube is wiped off with the lifters as the motor rotates, so the only lube the cam gets is from throw off from the crank and rods. A good cam grease will hang till it starts, IF the valve springs are fairly weak, but once running, it takes 1500 - 2000 rpm to throw enough oil to keep the lifters and cam from scuffing each other.

I have little doubt yours is probably OK, at the most, your valve springs are in the 60 to 70 psi range with very little cam lobe lift, compare that to a quality race spring in the 200 up to 400 psi range and you can see where lube can play a important part.

You did everything right, up to the point of starting. Next start up have everything ready, fuel, water, battery, and garden hose ( incase it start getting hot, cool radiator). Once started, keep it up in rpm, DO NO ADJUSTING TILL YOU ARE DONE WITH BREAK-IN PROCEDURE, don't let it get hot, and do your best to not shut it off.

With a stock 235, this may be total overkill, but why chance it. Its not just the cam that gets wiped out, the bearings also get trashed from cam material be imbedded in them along with bearing journals, lifters, and the oil pump. A total tear down and cleaning will be required if the cam is ground off.

Good luck,

Joe

Oh, now I got it! Thanks guys, that explains it. I'm a bit thick sometimes ;D

I did use a ton of that red startup engine slick on both the crank and the camshaft, but I didn't think of the cam not getting lube from a low rpm turn over. Makes total sense as to why you want to start it and run it at high RPM the full 20 minutes, right off the bat without much cranking.

I have to pull the oil pan to rebend that oil pump arm, so while I'm under there I'll take a look and see if any of the lobes are noticeably damaged. Even if they aren't, I see now why you're supposed to keep turning to a minimum before startup. Good information to know, thanks guys.

First sign of lobe trouble will be a loose push rod. Once the wear to that point, the pressure on the cam lobe is reduced and the wear slows way down. It will never recover since the outer material is ground off and the two mating surfaces are in the soft inner metal.

Look it over, add some lube if you want, and be ready next time.

Joe

The cam lube doesn't really stay on much after one pass of the lifters, I just did this and only rotated the cam one half revolution to set the other half of the valves, then when I was underneath putting the pan on, I looked at the cam, and the lobes that had gone through the lift cycle was wiped pretty clean with one single pass, now I realize it is only a microscopic film at this point but was interesting nonetheless

Yeah, that's a lot less than what I would have expected. I was thinking along the lines of the crankshaft bearings, where that engine slick actually stays on for a surprisingly long time. But since the lifters are actually 'wiping' or scraping, it makes sense that it knocks it right off.

The good news is that all my pushrods are just as tight as when I did the pre-adjustment... except one. One is just the slightest bit loose that I'm able to rotate it in its seat. That might be from me under torquing that rocker arm nut during the valve adjustment, or it might be from the cam wear. I guess only time will tell.

I'm taking a break from the engine to reassemble the rest of the engine compartment. Apparently the 'universal alternator bracket' I purchased wasn't so universal...

Thanks for the info though, I sure learned something new.

Yea, I bought a "universal" alternator mount for my 235 too. I'm pretty sure universal=sbc for the majority of manufacturers... LOL

Interesting thread!
I didn't know a stock 1950's 235 cam now needed such rigorous attention beyond the initial special assembly lubricant.
The "break-in" attention that I have seen from original literature focus's 99% more on getting the new rings broken in.
I am from Missouri, could someone show me?
Anyone got a source from Chevrolet {1930'-40'1950's ---Shop Manuals, Tech Service Bulletins, Chevrolet Service News others }on the change in the cam/tappett priority over the piston rings?

I am honestly getting confused on the 235 break-in that I will soon be doing on my 51' (I have my old lifters and cam on the bench in front of me and I am wondering what the last re-builder did right. or wrong).

Jack, the oil is what has changed. You still need to break-in rings just as your manual said to, only now we have the camshaft to worry about at the same time.

The zinc and other wear agents were removed from motor oils 5 or 6 years ago due to emmision standards of new cars.

Do a google search of motor oil and zinc and you will get weeks worth of reading. Some will be BS, most is spot on. Like I said in one of the above posts, it might be overkill for a stock 235, but is worth the money and time to chance it?

Joe

any information you get from the 30-50's won't apply to todays situation. Just use the cam companies (any cam company, they all have basically the same information) instructions.