Hi all, I've got some head gasket concerns on a 1.3 lump and was planning on a compression test to determine if it's HG or just short runs causing some mayo. The car is an early 1995 with 1.3 67bhp engine. Could anyone advise what typical compression values for this engine are?

Many thanks in advance.

8.6 to 1 i think, not so sure but i know is much less than 9

what is your problem with the head gasket ?

did you take out your spark plugs to read them (all 4 side by side)

i had some mayo problem just a couple of days ago, too out all my plugs they all read well expect cylinder #2 witch was carbon fouled, have no oil in the water so i'm thinking piston lining and over lean mix

now i get no more mayo and spark reads good had to change exhaust clearance to 0.25mm to clean up the oil coming in, but i guess that because of worn valve gide and the venturey effect in the valve stems

i feel i'm getting bad FE now, but will have to monitor to make sure is not paranoia

Sorry, I should have made it clear I was after typical PSI values for the cylinders, not compression ratio. Am I right to think I should be looking at about 130 - 140 PSI? Haven't looked at anything yet but the plugs will obviously have to come out to do a compression test anyway.

tbh a compression test wont tell you an aweful lot unless the head gasket has a massive blow, you need a block tester really, off the top of my head i think the compression pressures should be about 12bars which is approx 170psi

Sorry, I should have made it clear I was after typical PSI values for the cylinders, not compression ratio. Am I right to think I should be looking at about 130 - 140 PSI? Haven't looked at anything yet but the plugs will obviously have to come out to do a compression test anyway.

i would warm the engine up, remove all the spark plugs cranck the engine and test for a even compression on all the cylinders

i would also take the time to connect a vacuum gauge to the intake, and crank the engine it should give you 5 inches of mercury while cranking.

ectract from; Reading a vacuum gauge Speed reading

Cranking Vacuum & Speed Tests

You can get a quick basic appraisal of engine condition by connecting a vacuum gauge to the manifold and a tachometer to the ignition to check vacuum and rpm at cranking speed. Warm up the engine first, then shut it down and connect your test equipment. Close the throttle and disable the ignition, or use a remote starter so the engine won`t start. Crank the engine for 10 to 15 seconds and observe the vacuum and tach readings.

Note that different engines produce different cranking vacuum readings. Some carmakers publish specifications; others don`t. Again, experience will be your best guide. What you`re looking for, most importantly, is steady vacuum and cranking speed.

If the cranking speed is steady (about 200 rpm) and vacuum also is steady (around 5 inches), the engine most likely is in good mechanical condition. If rpm and vacuum are uneven, the cylinders aren`t pumping equally. The engine probably has leakage past the valves, rings or head gasket. If the vacuum reading is pretty steady but cranking speed is not, you`re probably looking at a damaged flywheel ring gear or starter. If the. cranking speed is normal or high but vacuum is low and slightly uneven, the engine probably has low compression or retarded valve timing. A jumped timing chain or belt is a common cause here.

you can't have a problem and have a even cracking vacuum and even compression psi on all cylinder...

again, i'm just a regular joe, not a mechanic, just like poking and reading (or the other way around)

best of luck and keep posting and let us know if you find the solution to your problem others can benefir from it (by the way, you din't say what was the illment)

i forgot to add, makesure you umplug the crank sensor if you are doing a compression test, that way it will isolate the fuel and sparks and wont start up

I'd agree, a compression test is probably going to tell you feck all.

Block test or a cylinder leakage test would be better.

How about sniffing the coolant with a gas tester to check for combustion gases?

Local friendly MOT centre had a look for me yesterday and found no trace of combustion gases in the expansion tank but agreed that the coolant was oily and the oil was wet (IYSWIM).

I haven't seen what a HG looks like yet but presumably there is a means for the gasket to have broken down between coolant and oil galleries, hence the cross contamination without exhaust gases being present? If this is the case I imagine it will all be in a pretty poor state.

I'm able to do the HG but the cost of these parts are similar to what the car cost as it was bought for a charity rally to Prague... I don't suppose anybody has a spare set of new bolts going begging do they?! Which HG set to buy is the next question, some come with valve stem seals, others don't. I need a rocker cover gasket too, so one including both would be best.

Hi all, I've got some head gasket concerns on a 1.3 lump and was planning on a compression test to determine if it's HG or just short runs causing some mayo. The car is an early 1995 with 1.3 67bhp engine. Could anyone advise what typical compression values for this engine are?

Many thanks in advance.

i just looked it up, if its the same 135 engine as the favorit is 11 bars, if its the 136 is more