Major Engine Repair Question

[lespaul]

I bought my 73.5 last summer and have put about 2K on it. Have done points, plugs, cap, rotor, valve adjust, oil change, trans oil change. Runs great. It has 179,000 miles on it.

Now, I am looking more carefully through the huge stack of repair orders the PO gave me. The only major engine repair items are as follows:

On 2/2/80 at 86,844 miles, car had "engine overhaul." This included "replace 3 exhaust valves, 12 guides, 1 disc, 1 pressure plate, 1 throw out bearing, 1 complete set rings, 1 pulley seal, 4 oil tubes" and other items and "replace clutch assemby, engine overhaul including valve job, ring job, complete re-seal, major mainentance, set cam-timing, set up engine, replace intake boots"

Then, on 4/9/82 at 98,340 miles, car had "rebuild engine complete and replace inner CV joints" The parts list includes "a $175 gasket set, 6 piston liners, a rod bearing set, main bearing set, int shaft set, oil pump, 40 valve shims, 12 valve guides, 1 valve." And there is a machine shop charge to "polish c--- & valves"

I am guessing the the engine blew in 1982 due to chain tensioner failure - but what do I know?. On 9/22/82, there is a charge for "two tensioner assemblys to replace the timing chain tensioners." Then on 11/4/88 with 132,000 miles, there is another replacement of timing chain tensioners.

On 11/19/90 with 142,000 miles, the chain tensioning sprockets were replaced , the timing chain replaced, cam sprockets were replaced, 4 new motor mounts installed, the Carrera chain tensioner kit was installed, new Carrera pressure fed cam oil line, four fuel injection valves, new oil pressure sender and a new clutch.

Oil changes and valve adjusts seem to have been done according to schedule since 1982 engine rebuild.

So, for those of you who know a lot more about engine rebuilds than I do - which is near to nothing, (besides regular maintenance) what should I be doing/looking out for/upgrading to protect and sustain my engine? Is there anything in these repairs that raises a red flag?

Thanks for your time.

[lespaul]

Bump.

[tonythetarga]

I am certainly not in the expert category, however it looks like the first rebuild was very minimal and may have been adequate. The second one two years later also adds an oil pump, which, if the old one failed while being driven, that could very well be the cause of the much more inclusive build the second time around.
Just for your peace of mind, you should have the compression tested and the leak down performed so you get an idea on engine status. Check your oil frequently and change it as required, but at least once a year for a low use/mile car.
The Carrera cam chain tensioners should perform well and remove that worry. The cars are pretty durable and should be driven hard once in a while.
I would make sure I do a brake fluid flush eash season for street driving and put in a high temp fluid.
Tranny fluid might be good to change as well, especially if you don't know when it was last done.

[lespaul]

Thanks Tony. Last week, tranny oil was changed. Brake fluid flush is next.

I will get compression and leak down test just to see . . .

[304065]

The first overhaul was a top because the case wasn't split and the bearings weren't changed. The second overhaul was an "overhaul" because the bearings were changed, but there is no mention of the rod bolts being changed, danger. I don't know what "piston liners" are, if the pistons and cylinders were replaced that's good, but there's no mention of a piston ring set, that's bad. It's bad to replace the piston rings without verifying that the grooves are in spec because they break in a couple hundred miles.

Bottom line is it's impossible to tell from the description. What would concern me most is the lack of mention of replacement rod bolts at the second overhaul. Factory bolts are a "torque-to-yield" design whereby they are stretched beyond the yield point into the elastic range and CANNOT be re-used without fear of disastrous consequences. Some say "real engine builders know that and change them" and I say "real engine builders write down every part number that goes into an engine, that's how they remember to CHARGE you for it!"

Bottom line: what do the leakdown and compression numbers say? Are there any other knocks or noises that are out of the ordinary? It's impossible to tell you "go for it" on those facts, unfortunately.

[Dirty Marty]

Lespaul,

Tonythetarga is correct in his advice. I would add that it appears the previous owner was diligent on Preventative Maintenance and that the best approach to take for a longer life. The valve train and the valves are the hardest working elements of the P-Car engines. I would be attentive to any drastic changes in oil consumption or smoking as it would indicate that rings or valves may have reached the end of their service life. The worst thing that could happen is to neglect that and have a catastrophic valve failure that destroys a cylinder, pistons etc.......

Keep a close eye on your oil consumption and oil pressure and react with any indication of quick change.

Dirty Marty

Fallbrook,CA

[Grady Clay]

Brad,

It looks like the original repair (2/2/80) was just a “top end” and rings, not a complete rebuild. I suppose it is possible that a tensioner/ramp failed and the engine jumped cam timing only bending three valves (no rockers replaced). I don’t see any chain ramps or other cam-drive parts.

It is also possible (more likely) that this was due to oil consumption/smoking. They tried replacing valve guides (finding three exhaust valves needing replacement) and installed new rings. Apparently it didn’t work as the next repair was 12K/2 years later and included pistons & cylinder. I think the reason for the 2nd valve job was to insure that it was correct (or the original one was poor). I suspect the oil pump may not have been necessary – those seldom needed replacement on a rebuildable engine.

It is interesting that the 4/9/82 rebuild again didn’t include chain ramps (something that should be changed every time) or anything else related to the cam drive. As you can see that 9/22/82 it needed tensioners and again at 11/4/88. Again no mention of ramps. I suspect these weren’t the “Turbo” tensioners available at the time. Is there any indication of the chain idler arm update?

It appears that the chain drive was finally addressed in 11/19/90.

It looks like you have about 47K on a complete rebuild with new P&Cs, valve job and the tensioner updates. I can’t imagine the engine still has original chain ramps but I would want to know that.

If the engine has good compression and cylinder leak, isn’t using oil and performs correctly, all it needs is normal maintenance. I would inspect the sump screen and oil filter.

A worthwhile project for you is to investigate all the options for your engine when it needs another rebuild 10 years from now. You have the very desirable 7R crankcase. You could build a 2.8S with MFI having spent ten years collecting parts.

Best,
Grady

[lespaul]

Thanks Grady, Dirty Marty, John and Tony

The part numbers listed on the invoice for the 1990 upgrade to the Carrera tensioner are 93010591100 and 93010591200. Pelican now lists these parts as "Chain Tensioner Kits" but does not say what is included in the kits. Back in 1990, each kit cost $240. The work was done by Competition Motors and cost the PO $4700 in 1990 -- this included new clutch and other things - wheel bearings and the like. Do you think that the 1990 "Chain Tensioner Kit" included the chain ramps? Grady, I see no indication of the replacement of a chain idler arm update -- unless that too was in included in the kit.

The car runs at about 183 degrees F - steady. It has climbed to 210 once on a 95 degree day in stop and go traffic, but returned to the 190 degree range thereafter. It does smoke sometimes at idle, but this is rare. I used less than a quart of oil in 2000 miles last summer. My only oil change - changing out the PO's oil, which was 4 years and only 1000 miles old (ouch) -- showed no metal in sump screen - just a tiny collection of fuzzy wool on the magnetic plug.

I guess the next step is to get the compression and leakdown test and hope for the best.

Oh yeah, I guess I should also start to collect those parts for a 2.8S with MFI.

Thanks again.

Brad