A sluggish 62 Lincoln sick with poor compression.

Hi everyone. I have a problem with my 62 Lincoln. She is one sluggish old gal. At one point I had two 62 Lincolns. The one I had to sell really could get on it. I sold it before I did a compression test on it to compare the two. My sluggish 62's compression readings are as follows: 1) 120 2) 125 3) 120 4) 125 5) 125 6) 125 7) 125 8) 130. I looked up what the compression is supposed to be and the manual said 190. Anyone have any ideas of what could cause such a large drop across the board? Do you guys think it could be a stretched timing chain?

 

how many miles on the engine? sounds like it needs rings. chain would just mess up timming not compression.

 

74,000 miles on the engine. My thought was that the valves may be opening/closing at the wrong time for each cylinder (caused by bad chain) and that this was possibly messing with the compression. It just seems strange that this is an across the board type thing.

 

How you checking ? warm engine ,all plugs out ,throtle blocked open? If you did not try it this way try again,still low add a couple of squrts of oil to the cylinder you are testing . Then try again ,comp now better ? if so bad rings. Forget the timing chain as it is not the problem. May need a valve job if comp does not come up with the oil in cylinders.

 

What is the exact description of compression the shop book is using?
Oddly a great many old cars with V8s have compression specifications in the 120-140# area, 190 sounds very very high.

Has the car been sitting quite a while?
Does it smoke?

Try a double tablespoonful of Marvel Mystery Oil or ATF in each spark plug hole, let sit for 24 hours, then start engine OUTSIDE! This will cause a massive cloud of smoke but when the engine gets to operating temp and then you drive it for a while, it may free up the rings as it did in my old Plymouth Woodie and several other cars I've had that were sitters for some months or years.

 

Did the compression test by the book. I did not do a leak down test then because all the compression readings were all around the same. Later I checked the shop manual and that is when I learned that the compression is really supposed to be 180 +/- 20psi. I will go ahead and do the compression test again along with the leak down test and see what happens

 

The compression in the book is listed as 180 +/-20 psi. I thought it was high as well, but that is what it reads

I have had the car over a year and I dive it regularly. No smoke either.

Thanks for the Marvel Oil trick. I will give it a shot

 

the good thing is that all numbers are within 75% of each other. very rarely does everything fail together, so i'm less concerned about the "180" spec. That said:

- did you warm the car up for a half our or so driving before the test? put some load on the motor before testing too.
- choke open?
- remove all the plugs before testing any cylinder?
- your gauge?

the consistency of ranges makes me get less concerned about the psi. maybe do a leakdown test to look at it from another (better) angle...

-scott noteboom

 

if the main sypmtom is that its sluggish, have a close look at your ignition system..is it advancing properly? vacuum canister not split? plugs/leads/points all good? any fuel system probs? clean filters and carb?
i wouldnt be super concerned about the psi readings if they are even, and above 120 on average.
I think youll find the sluggishness is a tuning problem.

 

I'm sure everyone will dismiss this - but Lincolns had a couple of mufflers on each side - something that old the muffler gets plugged up with junk flaking off from the inside. Happened to a 62 a friend had. Just no power...compression appeared to be acceptable range and percentages. His mechanic started it...revved it up....put it up in the air...disconnected the header pipes...VOILA!!!! - power up the wazoo - new exhaust system and the difference bordered on the miraculous.

just a thought...

dj

 

Valve timing off will lower the comp.

 

Thanks for your responses everyone! First, let me tell you all the things I have done to try and give the car more power. 1) custom dual exhaust w/ glass packs 2) petronix ignition w/ matching flamethrower coil. New wires and plugs. Timing set to the max that the manual recommends. 3)Holley street avenger 650 carb w/ 50 cc accelerator pump and tuned with the correct vacuum secondary springs. Electric fuel pump. 4 New air/fuel filters.

I have done vacuum tests and everything checks out fine in that dept.

When I did the compression test I did not have the car warmed up enough. I will do the test once again and also perform a leak down test.

I will also replace the vacuum advance and see if that helps

I can hear a bit of "chatter" when the engine is on. Valve problem perhaps? Where else would you guys look next to improve performance?

Thanks!

 

I agree with propwash and lowsquire, Sounds (more) like a tuning problem, or very possibly clogged exhaust, .............It's not likely that the compression readings you are getting would cause 'sluggish' performance. I know of oil burners with pronounced blowby that will burn the tires.

 

Has the engine been rebuilt or is it an original 74,000 miles. The early cars originally had quite a bit of compression until rebuilt with aftermarket pistons and or camshaft. May be the reason the numbers are down, just a thought.

 

Dont discount the shop manual's pressures. Those old MELs had 10:1 CR or more.

 

many fmco cars had exhaust pipes that are actually 2 pipes with one made inside the other >>>inner pipe collapes you canno see on theouter pipe ussually you will hear a whistle from the system if you are under car up on hoist...the lack of power gets worse the hotter the system gets

 

I wish I knew if the engine was a rebuild or not. I really have no idea. Same goes for the mileage.

 

This happened to a friends car. For mine, it has recently just had the exhaust replaced so something else is the cause.

 

What year 4V intake did you use? The 61/62 2V heads have smaller runners than the later 63/65 4V 430. Did you check runner alignment?

The PERTRONIX IGN MODULE has to have full battery voltage. If a PERTRONIX coil, it also needs full battery voltage. If an OEM coil, it needs to be powered through a resistor.

You also need to ascertain distributor vacuum advance and mechanical advance operation.

Restricted exhaust can be determined with a vaccum gauge.

Fuel pressure reading @ the carb?

 

Don't just ck base timing, make sure you ck timing curve and that it is advancing as rpm increases.
There used to be a test for the timing chain by turning the engine back and forth and cking the rotor movement

 

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We used to advance and retard camshaft until we got highest cranking compression. Timing chain has every effect on compression

 

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The car already had the 4 barrel intake manifold when I bought it. I haven't taken it off to see if everything lines up right. As far as leaks go, I don't think there is a manifold leak. Good call on checking the runner alignment.

The pertronix has the proper voltage and is hooled up as the directions say to do so.

I am going to replace the vacuum advance to see if that helps. The mechanical advance is ok.

The fuel pressure at the carb is ~5-6

 

The intial compression test is no good as it was not done with the engine warm.

Advancing/retarding cam events will affect CR as the valves open earlier or later (this will include a stetched or jumped chain).

These later MELS use the cam gear with the nylon covering so they are prone to failure and blocking the pump inlet with debris. A good mechanical oil pressure check should be performed also.

Just a thought(s)...

 

Additional imfo to restricted exhaust >>>look at bottom of air cleaner top cover for black burnt look ...also drive car w/o air cleaner top back hood open and look &listen for a strange roaring noise out carb or mist of fuel ...a badly retarded cam /chain strecthedwill show same >good pic collapsed inner exhaust pipe<

 

With such an across the board low compression it made since to me that it is something like the reasons you have stated that the compression is low and non variable in each cylinder. When I did the compression test I didn't do it with the engine at operating temp. I am going to do it over again and also do a leak down test. I will post what the readings later tonight hopefully. Everyone has come up with really good ideas. Thanks everyone!

 

Oops forgot to answer your questions 1) no loss of coolant or oil blow-by

 

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Just got done doing the compression test over again after the engine was warmed up.

Here are the readings: 1) 130 2) 135 3) 135 4) 130 5) 125 6) 130 7) 125 8)130
after oil in the cylinders: 1) 140 2) 140 3) 140 4) 137 5) 140 6) 140 7) 135 8) 140

Compression according to the shop manual should be 180 +/- 20 psi

After starting the car after the leak down tests, I had smoke coming from the valve covers. After seeing these readings do you guys think the next step is to check the timing chain?