The Stovebolt Site Forums The Shop Area Engine Shop T-minus a day or two

Greetings. I've spent the past 30 months rebuilding my '49 from the ground up. In a couple of days, I'll be ready to test-fire my '59 235 for the first time! I'm running some final checks, and I have a couple of questions.

First question - The fuel tank, fuel lines and fuel pump seem to be leak-free and working just fine. However, I have a glass filter bowl installed on top, near the carburetor. When I turn the engine over (with the key off) the glass bowl fills will fuel as it should. When I stop cranking the engine, the glass bowl drains back to the tank. Is it supposed to do this? In other words, the fuel is running backward through the pump and into the tank. This means at start-up the glass bowl is always empty, and the carburetor would not get any new fuel until the glass bowl fills. Should I care?

Second question - I'm told that when I start the engine I should run it for a good 30 minutes at 1500 to 2000 rpm to warm it up and break it in. Should I connect the vacuum advance during this break-in period or should it be disconnected?

Question three - Assuming the engine starts, what should I tinker with first... idle, vacuum, timing, valve clearance, or can I worry about all of this stuff later and just enjoy the moment?

Thanks!

Having a little apprehension prior to an engine start is normal (at least, it's been normal for me). Also, no matter what you plan for, be prepared for unforeseen surprises.

First question - the fuel level in the glass bowl fuel filter (at the carburetor) might go down a little, but if the bowl completely empties something is odd. Is the bowl orientated at the top or at the bottom (it should be on the bottom - post a picture of your set-up, if you can)?

Second question
- idle speed - (also see question three) do you have a new cam and a new set of lifters? If yes, follow the cam manufacturer's recommendations. Otherwise, set idle to 500-1,000 rpm.
- connect vacuum - yes, why not connect the vacuum advance during break-in?

Question(s) three - what to tinker with:
- idle - yes, set it to the speed you want (or, the speed recommended for cam break-in) - 500-1,000 rpm (as long as you have oil pressure - if you have no oil pressure, STOP the engine and ask for advice.
- vacuum - you can't tinker with this but you can watch it. If it is erratic at idle, or lower than whatever your Shop Manual suggests for good vacuum, you've got something that needs to be checked out.
- timing - sure, you could adjust this (maybe, for a start, to maximum idle speed or maximum vacuum reading while the engine is idling).
- valve clearance - this does not get re-adjusted until you have run the engine for 30 minutes after reaching a stable engine temperature. How have you set the "cold" valve clearances?

Do you know how to spin the oil pump to distribute oil throughout the engine prior to cranking the engine?

Good luck - stay cool - let us know how it goes

Question 1 - You're right. The glass bowl drains about 1/2-empty, not completely empty. So can I assume the fuel in the carburetor is enough to keep the truck running until the glass bowl fills?

Question 2 - I'm using the original cam and lifters, but cam and lifters have been resurfaced to meet original specs. The shop mechanic who rebuilt the engine suggested 30 minutes at 1500-2000 rpm.

Question 3 - Sounds like maybe I should do a rough adjustment on the timing "by sound" until I get maximum idle. I'll worry about the timing light later. I don't have a vacuum gauge. Maybe I can borrow one.

I have already pre-lubricated the engine by turning the oil pump with a drill. I'm seeing oil drip from the rockers. I've adjusted the valve clearance (with a cold engine) and also verified that I have spark at all of the cylinders. My truck is 95% stock, but I did replace the original distributor with Langdon's HEI.

Thanks.

Oh - I also checked the oil pressure gauge by blowing compressed air into the probe and the water temperature gauge by dipping the probe into a pan of boiling water. Both are working. Can you think of anything else I should check?

No luck. It sputtered and coughed and backfired repeatedly through the carburetor, but wouldn't start. Rotating the distributor made these symptoms slightly better or worse, but still no luck. My battery finally died trying.

It feels like a timing problem, but I'm not sure. I'm using Langdon's HEI. Langdon says #1 should fire 10 to 18 degrees BTDC. Is there an accurate way to figure out where this is on my '59 235? I know that every circle has 360 degrees. So, does 10 degrees BTDC mean 10 divided by 360 (=1/36) rotation of the flywheel? Should I line up the marks on the flywheel and then turn the crank 1/36 of a full rotation in the counterclockwise direction (observed from the front of the engine)? Any help would be appreciated.

First, line up the marks on the flywheel/clutch-housing (for #1 cylinder firing). That should be near enough to TDC for #1 cylinder. At that point, the input and exhaust rocker arms should be loose (have a gap). If they both are not loose, either you have poorly adjusted tappets or you are a full rotation off in your firing order.

The engine rotates twice to fire all cylinders - the timing mark comes around twice and you could be 360 degrees off for #1 firing, one rotation off. Just ignore me, if you aware of this - this is a common mistake made when restarting an engine.

If your engine "passes" the above test, then try your timing technique (my guess is that simply setting you engine to the timing mark should not cause your engine not to start).

If it's backfiring through the carburetor, you've either got one or more intake valves adjusted too tight, or your firing order is wrong. Take the valve cover off, and turn the engine clockwise from the front until #6 exhaust valve is closing and the intake is starting to open. The distributor rotor should be pointing to the #1 cylinder plug wire at this time. If not, rearrange the wires so the rotor points to #1, followed by 5-3-6-2-4 in a clockwise direction. Setting the timing with the electronic setup will be a little tricky, but you should be in the ballpark close enough to start by moving the distributor a few degrees right or left while cranking. It's much easier to set exact timing with a set of points or a GM HEI setup. I'm not familiar with the triggering process on the aftermarket HEI units.

Once the engine starts, confirm that you've got oil pressure and bring the speed up to 2,000 RPM or so for 20 minutes. It's OK to tinker with the timing to get the smoothest run, but don't worry about an exact setting at this time. Fooling around with timing and idle settings before the cam and lifters break in can result in a scuffed cam and rapid wear. The cam and lifters need the splash-oiling that increase crankshaft speed provides during the initial wear-in procedure. Unless the engine tries to overheat, don't idle it for at least 20 minutes after initial startup. Once the cam break-in is done, idle it down, shut it off, retorque the cylinder head, and readjust the valves. Now it's time to restart, and deal with final timing settings and idle adjustments. This procedure has worked for me for about 40 years, even on some very high-dollar round track race engines.
Jerry

Yeehaw!!! Go baby go! The engine started and purred like a kitten for a minute or two - then died when I tried to give it gas. I have plenty of oil pressure and no signs of trouble!

I made two changes and I'm not sure which one solved the problem. I installed new spark plug wires which are larger (8 mm vs 7 mm) and they fit my distributor cap better. These wires were recommended by the HEI vendor (Langdon). I also removed and reset my distributor making sure my timing marks were visible and #1 was on its compression stroke (same thing I did last time but maybe I screwed it up).

After it died I was unable to restart the engine, and now I'm not getting any spark at the plugs. Apparently some sort of electrical problem or bad ground. Nevertheless, today was a huge success. Thanks for all the help. How did we survive before the internet??

This was my approach. See reply by me 7/12/09

Advice appreciated

Video of the big moment...

http://rides.webshots.com/video/3084546690105353580VttGDQ