The New Engine - Part 6 - 05/02/2009

The day has arrived. Moment of truth. Breaking the engine in and finding out how all of our hard work has fared us... But a problem has occurred. The stock rocker studs aren't adjusting well and actually bent a pushrod slightly! Rather than deal with this, a quick conversion over to BBC studs is going to be performed. They are $25/set or $55 total out the door, but luckily I know this guy who lives in a van down by the well...

Stock Pontiac stud on the left, BBC stud on the right. They used nuts which hold their grip after being tightened, so they don't back off. You even get more travel on the BBC stud than you do on the Pontiac one, just use the stock Pontiac rocker arm and ball.

Studs are in on this side...

Another shot.

Engine stand is outside while we get it ready to go on the test stand! Luckily everything is "known good" or "new" on this, so we shouldn't have any problems... right????

On the stand and ready to fire!

And it lives! It sounds good too!

Continues running! Notice how we had to change the carb between this picture and the last... A SERIOUS vacuum leak had developed on that lean as hades 1978 Olds carb and it was all we could do to keep the engine running with 2 people and both hands. This different carb was much better.

Got a few oil leaks, but we'll fix those.

Engines get hot on break-in. This was with a clutch fan and an electric backing it up.

It looked simple, but it seriously wasn't. It was one disaster and problem after another. The new starter wouldn't turn off once turned on (oh noes!) and no starter would disengage from the flywheel. We chased that problem for 2.5 hours, only to find it isn't a problem at all once the engine started running. Once that was fixed, we had carb issues once it got running. We chased those for an hour. THEN once that was resolved, we had random misfires combined with it just randomly dying every 5-6 minutes. Adjusting the distributor advancing or retarding didn't give the behavior we expected it to either. I finally put a timing gun on it and noticed that the misfires were caused by no spark (no light) every now and again, followed by no spark for a second or two and then the engine dying. Hmmm... the ignition was going away. Checking the pickup to the ignition module showed a frayed wire that would work sometimes and not others... and it occurred in the middle of travel as opposed to full advance or no advance - making it a VERY random issue as opposed to a known one. A new pickup coil solved that.

Can't have a new engine being run and broken in without videos!

Running 0:10 - note water leaking from head plug and worn alternator belt squeaks...

Running 0:10 - carb adjustments

Running 0:23 - Breaking in continues with lots of oil burning off manifolds.

Well, another successful break-in. Sure isn't like they make it out on TV with lots of pretty shiny parts and everything going well, but then we all knew that, right?

Return to '75 Trans Am Page

Last updated May 3rd, 2009