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how can you tell what shape the engine is in

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J

jackag91

Jedi Warrior
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Jack's silly question for the day.

I exchanged a few emails with the previous owner yesterday. He is under the impression that the engine had be rebuild fairly recently.

Supposedly, it had a new cam installed but I don't know about anything else.

With out taking the engine apart, is there any thing I can do to get a feeling for how good of shape the engine is in?

The only thing I can think of is to use a compression tester.
 
There are three things that jump to mind - compression test, vacuum test and leakdown test.

Compression test should provide a good overall indicator of cylinder wear, condition of the rings, possible valve seat or cylinder head problems. Particularly if there is a substantial variance between cylinders.

Leakdown is kind of the opposite of compression, pumping compressed air into the cylinders and measuring leakage. Again, it will indicate cylinder and ring wear, but if there is air escaping you can also use a stethoscope to check where it's going. If you listen at the oil dipstick, for instance, you can hear if air is escaping into the crankcase. Listen at the exhaust for exhaust valve leakage, at the oil filler cap for valve guide leaks, or listen at adjacent cylinders for head cracks or gasket leaks.

A manifold vacuum test is pretty easy to do and can be a good indicator of ignition or timing problems, valve guide or seat problems, or vacuum leaks (carb, cracked manifold, etc).

If its a Spitfire, don't forget to check for thrust washer wear.
 
Jack, while the only surefire way is a teardown, there are methods that will give a somewhat accurate assesment.
In conjunction with the compression test, use a leakdown tester to judge the condition of rings, valves, and cylinder walls.
Check the condition of the spark plugs for proper coloration, evidence of fouling or overheating.
Remove the rocker assembly and check for wear on the shaft, and tips of the rocker arms. You can inspect the ends of the valve stems for wear or mushroooming at the same time.
You could set up a dial indicator on the pushrods, rotate the engine (by hand, of course) and check for proper cam lift. However, unless you know exactly what the cam profile is, this may not help, except to show major differences, indicating a worn cam.
Cut the oil filter apart and inspect for metal particles on the filter surface.
There are also many places that will do a spectrometric oil analysis, indicating bearing or other component wear. Here's one:

https://www.blackstone-labs.com/index.html

Hope this has helped.

Jeff
 
A down and dirty quick exam-

1. oil pressure when the engine is warmed up
2. Compression check on cylinders
3. Thrust washer play
4. Any oily residue in the exhaust pipes?
5. Valves going clickety clack?

this will give you point to start.

d
 
Tinster said:
A down and dirty quick exam-

5. Valves going clickety clack?
Click to expand...

Though if it is a wet-sleeve 4 cylinder, some clickety clack is good (i.e. if you can't hear them then they are probably too tight).
 
The BEST way is to start it and drive it....you'll know in a hurry.

We ALL are driving used cars...buying a vintage TR is no different than buying a Taurus or a Volvo...drive it!
 
I haven't reached any conclusions yet. When I bought the car it was running, but then it developed the "clunk" so it has been on blocks for the last 3 months as I have rebuilt everything behind the transmission.

I need to put the manifolds back on before I try and turn it over.

Unfortunately, I have to go out of the country for a month for work, so it will be a while before I get it back running.
 
jackag91 said:
I haven't reached any conclusions yet. When I bought the car it was running, but then it developed the "clunk" so it has been on blocks for the last 3 months as I have rebuilt everything behind the transmission.

I need to put the manifolds back on before I try and turn it over.

Unfortunately, I have to go out of the country for a month for work, so it will be a while before I get it back running.
Click to expand...
What kind of 'clunk'?
 
That "overhaul" may have been nothing more than putting new bearing shells in. I think Bugeye58 is correct in suggesting a tear down. All it will cost is the oil in the sump and gasket kit if all is well. Then you can go back with Payen gaskets like you should.

My philosophy is if a seller cannot produce a bonafied recent for the rebuild, it never happened.
 
YankeeTR said:
jackag91 said:
I haven't reached any conclusions yet. When I bought the car it was running, but then it developed the "clunk" so it has been on blocks for the last 3 months as I have rebuilt everything behind the transmission.
Click to expand...
What kind of 'clunk'?
Click to expand...

It was the differential mounts are worn out "clunk"
 
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