Engine and Transmission Tech

OK, thanks to a post on this forum, I figured out it is not my pilot bearing squealing but my rear main seal. Since swapping intake manifolds, my engine is producing vacuum on the driver side. When I pull the breather on that side, there is a woosh of air into the motor and the squeal goes away.

Thanks to Fred, DiDueColpi for helping me figure this out before I pulled the tranny!

So it has to be a problem with the intake install but what I am wondering is what exactly went wrong? I was very careful with the install and there are no external vacuum leaks. What would cause the engine to suck a lot of air into itself on one side of the engine?



Edited 1 time(s). Last edit at 03/24/2015 10:34AM by Brownwood.

Sounds like a PCV issue.

Motor just has 2 breathers on it. never had a problem with the Edelbrock Performer intake. If just adding a PVC valve would fix this, I'm all for it! It just seems weird that it is sucking air? I thought most of the time engines blew air out of the valve cover breathers.



Edited 1 time(s). Last edit at 03/24/2015 02:42PM by Brownwood.

Really good news!

Yes, Dan, I spent about an hour getting the tranny ready to pull B4 I figured this out. All I have to do is put the bolts back in, remount my slave cylinder and re-bleed it.

I am still a little concerned that one side of the motor is sucking so much air thru the valve cover and the other side doesnt really suck any. Is that normal?

Quote:

.....pulls lots of air on one side of the motor and none on the other side.

I'd expect both valve covers/breathers to have equal airflow - Are you sure that both breathers flow air, no check valves, no restrictions- how's your crankcase venting?
A normal closed crankcase ventilation system has an air intake/breather in one valve cover and a PCV in the other with crankcase gases purged to the carb base.
How about posting a description or photos of your current engine vent system.....then we'd have a better idea of how to help

No PVC system at all just two chrome breathers, one on each valve cover. It worked fine with the Performer intake but not so good with the Typhoon.

I am going to put an open PVC on at lunch, using a PVC valve on the driver side and just leaving the breather on the passenger side, and see how she runs. It wont cost much and figure its a good 1st step.

OK, I added an open PCV system to the car at lunch. It made no difference at all. If I remove the breather on the left valve cover, the squeal goes away but vacuum drops dramatically at the carb, engine runs rough and it eventually dies.

Again, this breather system worked fine when I was using the Edelbrock performer intake, I didnt even need the PCV valve. Now the engine seems more like a vacuum cleaner. Is there anything that could go wrong with a simple intake manifold swap that would cause the whole engine to become a vacuum pump?

Here's the setup I did today:


If I remove the breather as show, the squeal goes away but the car runs like crap.



Update: I added a new breather to the passenger side valve cove and all is quiet for now. Engine only pulls 14 inches of vacuum at 900RPM idle, much lower than the Performer but I guess that is to be expected for a 1500-6500 RPM intake. Shes probably a little lean in the primary circuit also.

More to come if that darn squeal persists.



Edited 1 time(s). Last edit at 03/24/2015 03:28PM by Brownwood.

Once again I should look at everything before I comment Keith. (re the pm's)
Your setup looks OK. I'm a little concerned that the breather caps don't actually breath.
I would swap that one out for one that works.
However you shouldn't have anywhere near that level of vacuum in the crankcase.
And pulling the breather cap should make no difference to the vacuum reading at the carb.
I suspect that you have a sealing issue with the new manifold and it's leaking vacuum into the crankcase.
I'm afraid that you are going to have to pull it off and check for leakage.
Either a gasket slipped or possibly there is a port mismatch. Debris from the old gasket could be holding the manifold up, or even some bad machining .
Anything that disturbs the head to manifold interface needs to be addressed.
If nothing is found there, then it's a good chance that the manifold is porous.
You can send it out for pressure checking. Or check it yourself.
Just get two strips of wood that will cover the ports. One for each side. Drill them out so that you can bolt them to the manifold with a couple of old gaskets.The intent is to seal the ports up completely.
Now fill the manifold with a thin fluid. Something like alcohol or acetone etc.
Look for leakage underneath

Hope it's an easy one.
Fred

Fred,

I do still think something is wrong, so I think that intake has to come off for some further checking. If I pull the one breather off, you could literally use the motor as a vacuum cleaner. I think you may be right about the leak somewhere.

Keith,
Was just looking at your pictures a little closer.
I can see what looks like the intake gasket on the left side of the engine.
It's sitting very high up on the head.
I'll bet that it moved and has opened up the bottom of the ports into the crankcase.

BTW nice hunting pics.

Live like you mean it
Fred

Yes, Fred. That gasket sits in little tabs on the head gasket and cant go any lower but its just not the right gasket. I pulled the intake last night and most of the intake ports were leaking. New gasket coming today. These small block Fords have too many gasket variations! :) Not like a SB Chevy where that gaskets are all the same....

Ha, I didn't even realize that by posting those pics you could view the whole album. Good thing its clean, no naked selfies or anything! LOL



Edited 1 time(s). Last edit at 03/26/2015 09:20AM by Brownwood.

Unfortunately, this whole intake manifold leak cost me a leaky rear main seal. Motor was completely dry before and now it has that annoying rear main seal leak. My winter 2015 project I guess...

No naked selfies?..... Then who's pictures were those?

Seriously, I didn't know that you could view the whole album either. I will have to remember that for my own protection.

Give that rear main some time. If it's relatively new it will probably recover.

Live like you mean it
Fred

Felpro 1262S3 intake gasket is the one I use - mainly because it was specified by Ford Racing for use with their GT40 aluminum heads - it's 0.065 thick with 'printoseal' technology.
[www.ebay.com]
Hint - if you use this gasket drop the manifold down using 4 long dowels to ensure it drops down straight over the gasket (the printoseal is pretty delicate)

Thats the gasket that didn't work for me with my GT40 heads. I am going with the Dird racing gasket this time which seesm to line up perfectly. That Felpro one sits up too high and the bottom of the ports dont seal!

Quote:

Felpro one sits up too high and the bottom of the ports dont seal!

?????????
Are your heads aluminum or cast iron - not sure that the Felpro 1262S is compatible with the cast iron heads.

They are GT40 cast iron heads.