91 Lincoln Oil Consumption... valve stem seals?

[avrfan]

my 91 towncar is burning more oil than it used to, but then also my overdrive has been out and it runs much higher RPMS on the highway because I can only get to 3rd gear. Does anybody know if the valve stem seals are really hard to change? I dread the complexity of working with the overhead cam setup.

Also, how do I figure out if its the rings or the valves that's causing excess oil consumption? I have been told many times that the blocks on these cars is really reliable and last forever, however I've been driving for like 30k miles without overdrive and so probably I've put alot of wear on the rings from those high rpms on the highway. The car has well over 200k miles on it. Odometer was broken for like 50k miles driving before I got the car and so I don't know the true mileage, could be high 200's

Thanks

 

[driller]

Google leak down test.

Most wont worry about it and simply continue to keep check of the oil level.

 

[avrfan]

ok, I did that. found some cool videos on leak down test on Youtube. I can do this. I'll do it when I change the spark plugs for convenience. I guess if its the rings, I'll hear air blowing into the oil sump and if the valves, the sound will be in the intake or exhaust. Now, what if the compression and leakdown are fine and its still burning oil? Is that possible?

Thanks

 

[driller]

Now, what if the compression and leakdown are fine and its still burning oil? Is that possible?

"Fine" is a relative term when it comes to compression and leakdown readings. The more important indication is the variance between cylinders. I would think if the tests are "fine" and it still burns oil, there would not be a major enough concern to warrant any repair work.

 

[pantherqs]

It's possible.

 

[KStromberg]

I had a 91 Town Car and with less than 140K on it I was going through about 2 quarts between oil changes. When I asked my mechanic about it, he said these cars were notorious for burning oil. I later confirmed that through some information here on the internet. Check your oil every time you fill up with gas and add some if need be. I personally wouldn't worry, and with your sort of mileage I would have expected you to be drinking oil a long time ago. It is most definitely either stem seals or rings as you presumed. I would be more concerned with the transmission issue you are having at this point. If you get a good tranny in the car you could probably drive this thing forever regardless of the oil burning issue. At least it is always getting topped off with fresh stuff.

 

[avrfan]

I was reading a book about how to rebuild for v8's and it was interesting to note in the troubleshooting section in the beginning it commented that if an engine is used for racing, high performace, or run at high rpm's it would increase the rate of oil burning. Since I have been driving this car on the highway without overdrive( slipping ), it turns some pretty high rpms. sometimes I cruise in 3rd gear at speeds between 75-80mph, so the engine is probably turning like 5000 rpm the whole time!

I never got around to doing the leakdown test. The compression tests ranged between 181psi to 209psi and most cylinders were above 190psi. That seems pretty good compresssion to me for a cold engine thats just been sitting without running for a while. I do believe its the valve stem seals and I am going to try and change those out anyways. I just need the special tool for compressing the valve springs. It looks like this:


Only thing is they are like $200-300 from the dealer but I have seen them on ebay and amazon for under $100 however some of them had bad reviews for bending and being cheaply made knockoffs of the Rotunda brand. Anybody have experience with these and know where I can get a good valve spring compressor for a good price?

Lastly, I cannot get the Right Passenger Side Valve Cover off because the rear lower bolt cannot be accessed. The space is too tight up against the Evaporator Box. I started removing the evaporator box but it just seems like so much extra hassle. Is there a special wrench or tip on how to get that last bolt out of the right valve cover?

Thanks

 

[avrfan]

Anybody know any secrets or tips for getting the passenger side valve cover off? I can't get my socket or wrench on the last rear bolt...
I'm thinking I might have to remove the evaporator box but I was hoping that there might be a special wrench that gets in there.
Other thing I was thinking is to put a jack under the engine and see if I can get it to tilt away from the evap box to give me more room.

Anybody who might have done this would know what I'm referring to. I have a 1991 (one of the first models of this style). I looked at
a 1993 in the junkyard and noticed that Ford redesigned the clearance for the evap box and the valve cover. It has more room than my
1991.

 

[driller]

Could be the engine mounts are tired and sagging?

Would it help if the engine sat a tad higher?

If so, use a block of wood and a floor jack to carefully raise the engine slightly on the right side. You may find it advantageous to remove the mounting bolt from the engine mount on the right side to get a smidge more clearance.