Inlet manifold on a Windsor 302

[ChrisL]

I've been told that it is imperative that I make an effort to fit the inlet manifold squarely on the heads to ensure that the coolant-jackets seal correctly. However, my first attempt at fitting the manifold resulted in a little coolant leaking onto the bell housing and my second attempt I think had it leaking into the valley and consequently into the oil. Now I say "I think" because I can't confirm it other than to say that I have a lot of coolant mixed with the new oil (no oil in the coolant though). I now have the manifold back off and I have also removed the heads to confirm that I don't have a head gasket problem and all seemed OK in that department.

Has anyone else had similar troubles getting the manifold to sit properly? My method of installation is to use quality gasket sealer on both sides of the gasket and then screw in two "pilot" studs in opposite corners (which I later replace with the correct bolts). I then tighten the bolts in the sequence recommended in the manual. Is there something else that needs to be done that I have missed?

PS I'm new to V engines. All my previous work has been on straights.

[Ron Earp]

Have the heads been decked? If so, how much? If a lot your heads might not line up with the manifold very well.

Is the manifold new? Was it ever cut to accomidate a lot of decking on the heads in a previous life? If so, then it might not line up with your heads.

Did you use gasket sealant stuff on the water passages with the gasket?

When I put these on I go bonkers with the gasket sealant around the water ports - never had a problem at all using this method. I have had problems with no sealant, and I have also don'e fine with no sealant. But with sealant, works every time.

I have also occasionally done them without the valley gaskets - again, just goop a lot of sealant on the front and back and then put the manifold in place. The corners where the head, block, and maifold meet also are sometimes problematical, but can be handled with more sealant.

R

[ChrisL]

Ron,
I used more sealant the second time than I had the first just to be sure. I would suggest that I even used too much given that some squeezed into the ports (no doubt would have affected the performance).

On the assumption that I have been given the full truth on the history of the heads, I know them to have had very little use. They were in fact used by FPV (Ford Performance Vehicles) on a test bench for a "few" continuous hours and have never seen road use as such.

Incidentally, the original reason for removing the manifold was coolant in the oil after the engine had overheated (faulty thermostat) but did not get over 140C. In this, I can confirm that the original manifold gasket was at fault, but the next two leaks can't be explained easily.

Also, for what its worth, I have placed a long straight edge ruler across both plains of both heads and blocks and all seems to be OK. Also, the engine seems to run quite smoothly so its unlikely to have any major unknown damage.

Is there any other location in the engine where coolant might leak into the oil maybe? Head warping that can't be easily detected maybe?

[Clay]

Ive never worked on v8's but i have worked on lots of smaller turbo engines before. Is the oil filter housing on that engine water cooled? On some engines ive worked on, a bolt inside the oil filter housing could loosen itself over time and allow the coolant thats cooling the housing to seep into the oil passages.

Def try putting a new gasket on this time, dont reuse that old one as it may be pushing coolant without showing definate visual signs of failure by looking at the gasket.

what intake setup is that?

[Ron Earp]

I'd check the intake manifold castings and make sure the flanges on both sides are parallel. If the heads have use they could be warped, but, that isn't common with SB Ford heads. However, it sometimes is not easy to detect, although a straight edge will tell even a pretty small amount of warpage.

Your methods seem fine. What gaskets are you using? Felpro gaskets for late model 302 (5.0L) motors are very good and have a raised rubber seal around the port. These hardly need any sealant, but I still use it.

Is your block square? Has it had any work to it?

R

[ChrisL]

Ron,
The first gasket (the one that leaked over the bell housing) was a genuine Ford part for late model 5.0L (felpro with raised seal). When that failed, I used a cheapie that I had lying around which was somewhat thicker of unknown material although it looked like a dense gasket paper of some sort. I’ve just bought another set of genuine Ford gaskets and about to have another go at it. I’ll have to come up with an imaginative way to determine if the inlet faces are parallel though. Maybe a trip to the local engineering shop is on the cards.

Clay,
* I use new gaskets each time I assemble the unit and replace the oil (the cost of this simple exercise is starting to add up).
* The inlet system is the Roaring Forties off-the-shelf item. Not sure where they originally sourced.