My friend just built a new 427 for his Firehawk. Today it started squealing form the engine bay. He took off both belts and it still squeals from the engine bay. Oil pressure is fine and not fluctuating. The engine does not want to idle and it takes a little throttle to keep it running. Does anyone have any suggestions out there? Thanks.

 

It's very possible it's from Cam bearings - Crank bearings - Con-rod bearings.
Squealing is not a good sound, especially if it's not coming from the belts.
Did he build the motor himself? Is the car an automatic?

I'm not suggesting to start and run it but if you do, take a broom handle and put your ear to it and place it on various points in the engine to determine where the noise is coming from at the engine.

Try that, check back...

 

Yes he did build it himself. The car is a 6-speed. I am not there to help him right now. We are doing e-mail troubleshooting. I will let him know what to check for. I know he installed billet main caps and I am not sure if he had them line honed or not. I have not gotten a reply back yet. Thanks for the info and I will let you know what he finds. It may take a few days.

 

Try the broomstick "stethoscope" trick. It really works and I've found the source of many noises.

Honestly, it may be a spun bearing so please don't run it anymore. If he wants to find the issue, then have at it.

It may also, maybe, possibly be the clutch/flywheel contact. How was it installed? Torqued correctly? I doubt this but it's still a small possibility.

 

I just got off the phone with him. He took off the front cover and it looks like the cam sprocket made contact with the retainer. Also the cam bolts rubbed the front engine cover. He could not get the cam out because the lifter retainers are not holding all the lifters in place. I am thinking that one of the lifters may have turned causing the cam to walk.

 

Very cool that he found the source of the issue and it was NOT bearings of any sort.

Did he use the stethoscope method I described?

I hope I helped...later.

 

I don't think he used the broomstick. I did send him the info you provided me and he went for the cam first and found the source of the noise. Now he has to find out how much damage it caused. Probably ruined TREX cam, lifters, and the lifter retainers. He is pretty bummed out because the last race of the year is next weekend. Being in Germany, he can't get the right headgasket in time to make the race. Thanks for pointing us in the right direction. I will update tomorrow on the carnage.

 

Ah...that stinks. If I had a set of gaskets, I'd shoot them over. I've been to Germany a few times, wouldn't mind helping him out. Hopefully, not much is ruined.

Tell him RED High Temp RTV works great in a time of need, to replace a gasket surface. I've used it before, let it tack up, then apply part and bolt down. Hell, I recently used some on my new drain for the bathroom sink. It works GREAT !

 

My friend call Thunder Racing where he bought all the parts. I am not sure who he spoke with though. Seems it may have slightly spun a rod bearing. He is in the middle of moving to a new city and starting a new job so the tear down will have to wait for a while. He is not sure if it is the rod bearings or not.

 

I would say it would be worth it for him to tear it down just to check. Prolonging the
issue or a possible issue can be bad and ruin motor parts beyond saving. It's good he's getting it sorted out.

 

The car will not be driven anymore. He did get to enjoy the power of the 427 for 700 miles. I get home in a month and a half and we are going to tear it down and see what's wrong. I can't see why it would spin a rod bearing though. Everything was brand new parts and bought as a set. I guess the ole micrometer might have helped out on this one.