Well, I found my coolant leak. It is from the passenger side intake manifold, near the front. So I'll have to deal with what I've been putting off for a long time. There have been oil leaks from other parts of the intake manifold gaskets that I've just been patching with RTV silicone rubber. I'm looking at my Haynes manual right now for ideas on replacement.

Does Fel-Pro make a complete gasket set just for this? I'm guessing that I will need the intake manifold gaskets, the gasket between the upper and lower air plenums, and valve cover gaskets. Also, which of this site's sponsor should I be ordering from for best prices? I remember the "good" version of the valve cover gaskets being pretty expensive.

 

try retorquing all the bolts first on intake manif. plenum.....these work loose often especially on 4L

try calling several of the online suppliers, most have 800 parts order info numbers...ones i have dealt with are knowledgeble and willing to help with questions....there are several dealer shop parts counters listed in sponsors and also aftermarket....i've dealt with several, haven't found a bad one yet....they wouldn't last long here on a Ford site if they didn't know their right stuff and deliver support

 

I've already removed all the nick nacks around the engine, and loosened everything so that they will just lift off when I'm ready to install again. Interestingly, there was a loose bolt, but not where the coolant leak was. The coolant leak was at the front passenger side, where the lower plenum was still being held down tightly by the stud and nut. The loose bolt was at the rear passenger side, where nothing was obviously leaking. The rear driver's side is where one of the oil leaks is. The other oil leak is also at the front passenger side.

The new gaskets should arrive before Friday, when I'll have time to get to it again. I did a google search and found the best price at a most unlikely place; Amazon. They also had an additional discount until Jan 31, which more than paid for the shipping.

 

there is a difference between quality of gasket brands just as there is a difference in quality of women.....

cheaper in either is not always better


use acetone to do the final wipe on all metal sealing surfaces to remove oily film for best gasket adhesion

 

Fel-Pro MS98005T Intake Manifold set, including valve cover gaskets, retail $150+, Amazon price $51.45. Build the order up to $100 to get a $20 discount.

It was dark by the time I got everything taken apart, so I will wait until next weekend before I get to the real cleaning. The old gaskets came off surprisingly easily; I don't think I'll even need to scrape much. But I did spend a not-insignificant amount of time scraping off the RTV that I applied earlier to stop the oil leaks. Properly applied, that stuff is tenacious.

I now have a real appreciation for the Ford mechanic who replaced the valve cover gaskets on this van back in 1994. In by 8am, out by 4pm. It took me about 8 hours total just to get to this point.

 

xlt,

good going....yep, these new shop mechanics have nightmare flat rate repairs to do and still put food on the table....most are physically finished by the age of 50....too much artharitis in hands and back

 

The gaskets arrived this afternoon, and I was able to assemble most of the large parts. Fel-Pro included a small tube of RTV to work as the end seals; there were no traditional gaskets for the ends.

I have a question about a small part, because I can't remember how it was put together. I broke the large nipple off of the PCV valve that had the hose going to the upper plenum. I've epoxied it together, leaving some generous fillets to give it some strength.

There is a smaller nipple on the PCV valve, and I think it had a rubber cap on it when I took it apart. But I can't remember for sure now, because it is located near the vacuum tree where there are other hoses and caps. Can anyone verify whether that smaller nipple was capped or connected by a hose to something else?

 

hope that helps

M

 

Thanks for your picture Mormakil. My engine is a 4liter, and the canister purge lines are slightly different from those of the 3liter. In my case, the lines are semi-rigid, and the other side of the solonoid goes into a fitting in the throttle body, right behind the plate.

After I posted the question, I had the brilliant idea of looking at my 91 van with the 4liter engine, and it's different yet; its PCV valve has only one nipple, whose connection goes into the same fitting on the upper plenum, which is turned to point to the back, instead of down on the 90 model. So I guessed that the smaller nipple on the PCV valve must have been capped, as any nearby lines would also go into the same upper plenum area. But that PCV valve is so fragile, I swear it will break if I just sneezed on it.

Everything is back together now, and after a few seconds of cranking to get fuel back into the lines, it started up. There are no obvious leaks yet. But with the dog house cover off, I definitely hear a ticking noise. GRRR!! I'll have to chase that down after I find my engine stethescope. I don't remember if this was the case for the 4 liter engine, but the 2.8 liter had some kind of adjustable cup for the upper end of the pushrod that can be used to change lash settings.

Just waiting for the next leak...head gaskets...

 

Hi Eugene:

The PCV has one large nipple that routes the crankcase air to the intake manifold.

The small nipple you saw on the PCV is supposed to be connected to the Canister Purge Valve, which would go through the same large hose into the intake manifold anyway. That's the setup on some cars.

The 4.0L is routed slightly differently, even though the end results are identical. Take off that plastic part on top of the PCV and put the large hose on it directly. The other end of the hose goes to the front of the intake manifold, just as before. This way, you have gotten rid of that small nipple that was rubber-plugged anyway.

Now run the line from the Canister Purge Valve directly to the vacuum three on the rear of the engine.

Just draw a little diagram, and you will see that the end results are identical for both setups. What I described to you is exactly what I had on my '95 4.0L. A new PCV would come with the top part, which you can just remove and throw away. However, as a side note, that plastic piece is perfect for the Canister itself, when the little special hose (with a 90 degree bend) is busted there.

As for the lash settings, it's not adjustable on either of the Aerostar engines.

 

Thanks Tung,

I eventually installed the PCV valve with original routing by lifting up the rear of the upper plenum enough to clear the elbow hose, and gently setting it down again while pushing the hose onto the plenum fitting, taking care not to put any stress on the valve. It seems to be holding for now. If it breaks again, I'll try your suggested routing.

Looking back a little, I found the source of the leak at one of the front water passages between the head and intake manifold. It seems to be such a common problem that Fel-Pro describes it in their installation instructions. The problem must start with some seepage of coolant past the gasket, which then causes the metal (the cast iron head surface) to rust and pit, which then further weakens the seal. Fel-Pro warns to not use RTV to try to cover the pits if they're severe. I don't think mine was too severe, so I did use some grey Permatex RTV. It sets a little stiffer than the other stuff. I've only driven it for a couple of hours, and so far, so good. I'll be keeping an eye out for leaks, for sure.