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Shane P
13-04-2010, 22:39
WOT with a slightly warm engine gave me :

1. 150psi
2. 125psi !
3. 140psi
4. 130 psi !

dry.

Maybe should start building mini engines, i may have more luck with them :(

Something is buggered. It runs like you have just kicked it in the nuts. Wants to decelerate off throttle quicker then normal. Pops loudly out of the exhaust, i mean like its backfiring. Will only idle when it wants to.

Some kind of leak can be heard from inside the cabin, although i cannot locate it for the life of me. I have been over everything ignition and air pipe related.

Water is staying at max, oil seems to be staying put too, it gets to coolant temparature a little quicker then what i have come to expect as normal, hovering under the 90 degree mark and only taking about 10 seconds for the fan to kick in when i come to a stop.

A blast on WOT on 20psi will make the temps go level and nearly over the third line easy.

A good long steady drive on low throttle will only bring the temps down to about 60% or so on the gauge and it doesnt stay there long. At least me oil cooler pipes aint bursting anymore.

Time to take the head off?
Andrew Cooke
13-04-2010, 23:04
pipes to the cabin are factory boost gauge (try blocking where it joins the 4 way at the side of the carb.

or - aftermarket boost gauge or boost controller.
Shane P
13-04-2010, 23:19
pipes to the cabin are factory boost gauge (try blocking where it joins the 4 way at the side of the carb.

or - aftermarket boost gauge or boost controller.

Thankyou, they will be double checked tomorrow morning :)
Spooky
13-04-2010, 23:28
Could be valve clearances maybe?
Shane P
13-04-2010, 23:36
Could be valve clearances maybe?

Ah ha, could be Mr T, if these were out, do you think it would give me abnormal compression test readings at all?

I am pretty sure all the pushrods are straight :crap: and the clearences were set at .15 and .20, but i suppose all of that could have moved or changed for some reason?

I am barking up the wrong tree again arnt i :)
Spooky
13-04-2010, 23:42
Since the rebuild, have you redone the clearances?

Uneven compression could be down to that, as you're mentioning a hint of backfiring too.

Worth a check before you pull it apart. Do another comp test when stone cold just out of curiosity too :)
Shane P
13-04-2010, 23:46
Since the rebuild, have you redone the clearances?

Uneven compression could be down to that, as you're mentioning a hint of backfiring too.

Worth a check before you pull it apart. Do another comp test when stone cold just out of curiosity too :)

Will do, i can see why they made you Area rep, fair shout :agree:
Brigsy
13-04-2010, 23:46
Id adjust the valve clearances first as spooky suggested. Also try a drop of oil down the bores that are low on comp to see if it makes any difference that will tell you if rings are worn.

Something does sound a miss if the temp is flying up on boost, is cooling system pressurising? might be worth doing a sniff test on coolant to check for exhaust gasses.

As for poor idling/lean overun that could be classic blocked idle jet, mixture needs adjusting/screw missing or air leak on inlet, poss split breather pipe or restrictor missing.
Spooky
13-04-2010, 23:52
Nice one Brigsy :agree:

Shane, I asked, it happened, simples :p
Shane P
14-04-2010, 00:03
Id adjust the valve clearances first as spooky suggested. Also try a drop of oil down the bores that are low on comp to see if it makes any difference that will tell you if rings are worn.

Something does sound a miss if the temp is flying up on boost, is cooling system pressurising? might be worth doing a sniff test on coolant to check for exhaust gasses.

As for poor idling/lean overun that could be classic blocked idle jet, mixture needs adjusting/screw missing or air leak on inlet, poss split breather pipe or restrictor missing.

As far as i can tell, the cooling system is developing more pressure then normal, running on a stock fan switch and stat of course.

Fantastic, so:

1. Adjust valve clearences
2. Dry comp test with cold engine
3. Wet comp test on the lower reading cylinders
4. Coolant sniff test
5. carb/intake leaks

I will find out how to do a sniff test, anybody wanna fill me in :) not sure how to test the inlet manifold? Block the carb inlet and breather pipe and rev it maybe?

Idle jet cleaned a couple times, no missing screws or seals that i can see, gave me a perfect 1.6 'whatever it measures in' on the MOT emissions testing a week ago, something wierd has happened since then :( . I suppose everything has moved now that the gaskets etc have settled?

The breather pipes are new and will be checked again :) Is the restrictor small enough to suck into the one-way valve? Would a buggered one-way valve contribute to my problems?