top end rebuild

[Turton]

Hello everyone, so I did a compression test on my 66' series 2a 2.25L Petrol. here is what I got-90,85,87(est),85.
I like that there doesn't seem to be any big drops but the numbers seem low. I have no clue when or if the engine was rebuilt last. would you suggest a top end rebuild? no blue on start up ( unless I flood it), starts great actually, just has a hard time on the hills. not expecting Porsche like speed but I watched Barry the other day with his green rover with a trailer and I don't thinks mine could pull one.
anyhow any advice would be good.
thanks
Geoff

[Rambler]

Hello Geoff,

A quick search on the Series 2 club forum had this as a reply to a similar query on low compression for a 2.25 petrol engine.

"That's a pretty worn/tired engine - you did hold the throttle fully open whilst cranking, it makes a difference...
Normally you'd expect figures in the 160 to 170 for brand new engine, for one in good nick around 150 to 160 psi. You'd expect each cylinder to be within 10% of the others...."

Unfortunately, it sounds like the engine is a little tired and could do with a rebuild. I've yet to do this on my own S2 project so I'm worried my engine might be in the same position. :?

Good luck,
Ian

[red90]

The normal way to check if it is rings or valves is to do the test dry as you've done. Then squirt in some oil to each cylinder. If the compression goes up, it is rings. The head comes off in an hour if you want to have a look.

[Turton]

I did not have the throttle open, or squirt oil into cylinders. I will try this tomorrow
thanks for the info
Geoff

[island dormy]

Hi Geoff

As already mentioned to do a proper compression test the engine has to be hot, the valves set correctly, the throttle jammed wide open (good time to check that the throttle is actually opening all the way) and all the plugs out. Do each cylinder a couple of times to make sure you got a true reading. Then you repeat the test with oil, squirt a couple of shots of engine oil down each plug hole just before you check that cylinder. If the reading goes way up the rings are worn.

You could be low on power for many reasons a good complete tune up which includes setting the timing correctly may help?

Good luck Victor

[Turton]

Victor, thank you for the proper way to check compression. I just finished doing it the way you suggested. Results are as follows. Distributor off, choke on, throttle wide open-110,111,100,100psi
After putting about 3 tbsp of oil in each cylinder -128,131,121,110.psi
These are estimating as the gauge goes up by 10's.
So if I read this right I need rings! Or a 200TDi
Thanks Geoff

[island dormy]

Hi Geoff

The choke should not be on as this would restrict the amount of air getting in for the test. Is that a typo?
But if those are the actually readings they are low and the motor would be low on power.

Good luck with your rebuild.

Victor 1962 Dormobile

[Turton]

Well round three in compression testing starts tomorrow. Not sure why I thought the choke had to be on. Oh well, I'm getting experience at least!

Thanks Geoff

[Turton]

Ok let's try this again.
Compression test 3, throttle open no choke.
100,100,108,100
After 2 tablespoons of oil in each cylinder
115,125,125,115
Still seems low. I think rings and valves are in order.
Your thoughts?
Geoff

[island dormy]

Hi Geoff

Yes your results do seem a bit low. My 2.25 engine with 8 to1 compression and 10,000 miles on it reads around 154 with no oil, adding a table spoon of oil and repeating the test they jump up to about 160 which is normal for this kind of test. ( A 5 pound increase is considered normal). That you have such a big increase when adding oil shows that the rings may be worn.
Even if the gauge you used is reading low the difference in the 2 tests is to large.
It is kind of strange that you got higher readings on some cylinders with the choke plate closed on a previous test? Maybe the rings are a little stuck or dirty? Maybe running some kind of engine flush through the motor then changing the oil and filter and putting in some good 20-50 might help? Just guessing I am not a expert and this may not help at all?

It may run the way it is for many many more miles. You did say it is not blowing smoke. If it is tuned up correctly which means the timing is correct and advanced as far ahead as possible with out pinging occurring (usually 3 to 6 degrees before top dead centre) valves set, points set, plugs gapped correctly, throttle opening all the way, no brake drag, proper size jets in the carb etc. you should be able to hit 60mph easily 65mph with a bit more effort and 70mph with a really long runway and no head wind.

Good luck.

Victor 1962 Dormobile

[Turton]

Thanks for the advice, the truck runs smooth, it doesn't even come close to 70 MPH, on a good day it will do 70 KPH. I will price out a set of rings and top end, not sure if my skill set can tackle this job. At least I have a Land Rover repair guy across the street from my work.
I will keep you up to date.
thanks
Geoff
side note, I did get my collector plates for it today

[red90]

If you are doing a full rebuild you can't price it out in advance. You need to take it apart and see what needs to be replaced.