Engine problem... Compression test results... (translate??)

[vibrating_Cake]

right the saga continues lol, got lots of steamy smoke coming out of the exhaust now, with a few backfires and firing from the carbs... so...

 

compression test, i did the first one with the engine "mild" it had been sat like 40minutes after being warmed up cause i was hungry lol.

 

all these were taken with throttle fully closed (if that matters?)

 

from headlights to bulkhead 1-4

DRY

 

50psi

50psi

113psi

110psi

 

WET

over 300psi

145psi

200psi

225psi

 

wet fully open throttle

 

off the scale

off the scale

290psi

off the scale (bearing in mind the scale goes upto 20bar!

 

then.... i warmed the engine up and re-tested....

 

WARM non open throttle.

 

100psi

98psi

152psi

152psi

 

Fully open throttle

260psi

260psi

237psi

250psi

 

fully open WET

285psi

287psi

257psi

275psi

 

without fully open throttle the results may be because the carbs havent been balanced, as the front2 carbs are getting less pressure each test...

 

 

but... can someone translate any of these readings.... is this bad news for my engine block???

or do i need to do more tests/do the tests a different way?

 

i must admit the engine wasnt FULLY warm, as it was smoking out the street (ill add a vid later!)

 

help? lol

[Jimbob-Squarepants ©]

Fully open throttle

260psi

260psi

237psi

250psi

 

fully open WET

285psi

287psi

257psi

275psi

 

You should always do your compression checks with the throttle fully open.

 

Number 3 is a bit low, but I would say there isn't much wrong there. Have you got a Haynes or Autodata book to find out what the compression pressures should be? If not, give Ford a call and ask

[cisco24uk]

Headgasket leaking between 1 and 2. odds on.

[vibrating_Cake]

also......

 

the smoke!!! argh...

 

which only comes out of... cylinder TWO

 

ive just had the head off and re-built it lapping in the valves hope its not the headgasket... well... i do...

but if i strip the engine down, how do i know if the piston rings etc are nackered??

 

its never really run on cylinder2, the plug is always wet and dark colour .

 

neway vids =)

 

 

[mk2dk]

Always fully open throttle and normal operating temparature if possible, when doing a compression test. I don't think there's anything wrong with our numbers.

[Jimbob-Squarepants ©]

The idea of doing a wet compression test is to diagnose if there is any wear on the bores and/or rings. By your results, I would say that you don't really have to much to worry about. As I mentioned, number 3 is slightly lower than the rest. When my pre crossflow went bang, number three was really low, but the problem was with number 4 which had a good reading.

 

If you take the head off, you have to fit a new head gasket anyway, so that will eliminate that. Just have a good look at your bores, they shouldn't have any scoring and should be nice and smooth.

 

What ingnition system are you using? Oh and what spark plugs have you got in it???

[vibrating_Cake]

The idea of doing a wet compression test is to diagnose if there is any wear on the bores and/or rings. By your results, I would say that you don't really have to much to worry about. As I mentioned, number 3 is slightly lower than the rest. When my pre crossflow went bang, number three was really low, but the problem was with number 4 which had a good reading.

 

If you take the head off, you have to fit a new head gasket anyway, so that will eliminate that. Just have a good look at your bores, they shouldn't have any scoring and should be nice and smooth.

 

What ingnition system are you using? Oh and what spark plugs have you got in it???

 

err i just got new spark plugs not sure ill look tomorrow. the car ran perfect... until it dropped a valve and since then cylinder 2 has always had a wet plug and never really fired dno if its due to fuelling or whatnot.

 

but once i did the valves the car purred..... but then it went downhill from there.....

 

replaced valve stem seals and lapped all the valves in, doing a test by filling the ports with water and seeing if they leaked (they didnt)

but if i have the head off i may aswel check these for strange marks since i did it.

argh.

 

ignition system is Alpha management, which came with the carbs.

i thought it might be the plugs n leads but ive changed all of those (why the 3rd cylinder isnt firing)

and tried screwing the idle mixture screw all the way in or all the way out but nither helped that cylinder fire.

[Fiesta Steve]

 

its never really run on cylinder2, the plug is always wet and dark colour .

 

 

Choke stuck 'on' on number two cylinder ??

[vibrating_Cake]

 

its never really run on cylinder2, the plug is always wet and dark colour .

 

 

Choke stuck 'on' on number two cylinder ??

 

ooh... can they get stuck on on one cylinder???

i dont use the choke, just determination on cold mornings lol

[Fiesta Steve]

 

its never really run on cylinder2, the plug is always wet and dark colour .

 

 

Choke stuck 'on' on number two cylinder ??

 

ooh... can they get stuck on on one cylinder???

i dont use the choke, just determination on cold mornings lol

 

Yes, I've had this after trying for a while to find the reason for a black plug.

 

Remove the two screws that hold the choke cover on at the back of the carb. There are two fuel enrichment wotsits that should slide up and down freely. If they are not used, like yours, they can't become siezed in the on position if you operate them at any time.