Hey All,

I have an 85 Deville that I'm bringing back to life after it threw its timing chain and was parked for a year. It has a HT4100 v8 in it and from what I've heard and seen on this forum (Thanks everyone!!!), I've decided to go further and replace the camshaft and lifters. Does anyone have any other areas they would recommend investigating/fixing while I'm in there? Is there anything else that was known to go? It has 145K on it and I don't know its history other then it was working fine before it died.

Here's what I've gathered so far:

- The cam shafts were known to be short-lived, hence the replacement
- GM Coolent pellets should be used every 40-50KM (in canada, KM here) after coolent flush
- I also heard the oil light would flicker at stoplights & had a new oil pump added, so I'm going to replace the switch if the problem is still there after I'm done
- The radiator is toast, so it's getting replacement

Anything else? The body on it is good, so I'd like to keep it running for a while ( not to mention much nicer then my old 91 sable :). I'm aware they were not known for their reliability, but if I could get a year or two out of it I'd be happy.

Any advice welcome!

Thanks to everyone that's been posting info here, it's taught me a lot (and my friend who also has a 81 fleetwood w/368 v8-6-4 & 80-something brougham w/305)

Hi Wingman x!
I've got an 82 Seville with the 4.1 V-8 in it. It runs like a charm! I've just replaced the starter and the fuel pump. Just working on the interior and exterior of the Caddy to get it back to new looking -- no dents at all, just little bits of rust in areas, but otherwise in great shape. When I got my Seville 3 years ago, all I had to do was replace the air shocks in the back, tune-up, oil change and new tires. In three years, all I've replaced is the water pump, belts, smog pump (air pump), brakes all around (rotors, calipers and brake pads) and exhaust ( I had the cat cut out)... and new battery. Not bad for 3 years... I hope you have good luck with yours! Actually some people think this is a newer cadillac...
My oil light came on two weeks ago and the mechanic who worked on the fuel pump worked on the wiring and said that the oil light had a bad ground.
I drive my car all year round 70 to 80 kms every day. I like this motor with the 4 speed tranny.
Cheers! :dance:

I think you'd want to check the distributor gear for wear and replace as needed. Yours is an 85, the primary cars with high cam lobe wear were manufactured before January 1983, to that may not actually be an issue for you. Check to make sure the intake gasket is good.

My HT4100 has 115,000 miles and runs like a top. With proper maintenance, these engines can be durable.

about the durability, how does a little (1st couple of crank rotations after it catches) knock/chattering take off from the life span of the bearings, from not driving the car for a few days? (emtpy oil passages and bearings) I don't drive mine very much, but it's only got 50k on the motor, so I would like to not be a cadillac killer.:p

Thanks for the feedback guys! I have one more question for everyone: This car was equipped with a fiberglass timing gear which lost it's teeth , hence the thrown chain. I don't see any teeth/fiberglass bits anywhere, :hmm: is this going to come out of the oil flush I do when I reassemble the engine, or should I be looking somewhere else for these? Should the oil pump be pulled & checked? thanks!

Catillac:
The cat's in this are original, so I'm assuming they are almost toast, so I was going to ditch them and get my buddy to make a replacement straight pipe. When you did this, did you notice a difference? If so, what did you find?

Leftoverture:
I'll try to check the distributor gear as well, though I may be in trouble in that area. One of the bolts on the disributor cap snapped on me due to corosion, :banghead: so I'll have to fix that & will take that all apart. Thanks for letting me know the timeline, I was wondering if they fixed the cam wear issue on the 85 or not.

SolidGoldStein:
I had this same issue with my 91 sable. I had a number of things recommended too me, but I don't know how valid they are. First was not to use synthetic since it's viscosity is somewhat thinner then regular oil. Second was to try a higher weight oil depending on where you live (10w30 in the winter, 15w30 in the summer). Third was to try some anti-nock in the engine every oil change. Personally, I tried the anti-nock once (worked for a while) and switched to 10w30 all year round and it hasn't changed in 2 years. Hopefully someone more knowledgeable will post a more valid suggestion :)

Your cam may be perfectly fine if the engine was maintained with occasional coolant changes and the use of the coolant supplement pellets. The cams were actually fine....the problem that caused cam wear was coolant intrusion into the crankcase at the deck face seal of the head gasket. That whole thing was not much of a big deal by 85.....

Definitely check the distributor gear for wear before taking the cam out. If the distributor gear looks good with just nice, even shiny contact patches that are consistent around the gear then likely the cam is fine. You'll have to get the distributor out and apart anyway to change the cam so fixing the problem with the cap holddown is going to need to be done anyway.

The gear teeth on the cam driven sprocket are not fiberglass....they are molded nylon. Likely they are all in the oil pan.... May not cause a problem but they could start to clog the oil pickup screen and cause low oil pressure. If the gear teeth are all missing I would drop the pan while you are in there and clean it out.

Since we don't have an air-care facility where I live, I don't have to get my emissions checked like I would if I lived in the city. This is why I got the cat cut out. My car/engine runs great (actually more power and smoother than before), maybe my cat was done too. I don't think this messes with my oxygen sensor, no problems in the computer. Last tune-up I did was last summer, so today I took one spark plug out to see what it looked like and it was completely clean. Then I took the distributor cap off and cleaned the inside -- scraped light crude off contacts -- and cleaned the rotor with some emery cloth. I was going to take the EGR valve off and clean the inside but the bolts are hard to get at... I'll do it another day. Oil change next week. :coolgleam