smoky jo 20l 16v on twin 40s

[leeroy20vt]

hello boys and girls after a bit of advice just got my conversion running apperently engine been standing for a number of years

when first started all seems good bit rough on tickover but thats all give it a few revs and let it tickover agin it begins to smoke then if u rev it again u get loads of smoke 

also noticed that only one carb seems to be running on tick over if u put ur hand over carb that is inline with 1 and 2 it trys sucking ur hand in but 3 and 4 hardly anythink

and if u take plug leads of 3 and 4 it doesnt make a difference at all until u try reving it

could this be a sticky/bent valves or oil seals

or am i barking up the wrong tree here


any help would be great
lee

[danny_p]

chould be meany things.

pull the plugs first off, and comapre them,   then do a dry compression test followed by a wet compression test.

it's more than likely going to be a head off job.  the missmatch pulling of air choudl just be really badly set carbs.  but the smoke is the worry, if it's comeing from 1 cyl  it's proaby piston if it's a pair it more likely to be head gasket. 

the loads of smoke when revving shouts piston to me.  possobly just stuck rings possobly hole

[leeroy20vt]

thats not good then 

[danny_p]

smoke on startup = seals.   smoke when  reved / loaded normaly  = metal

[leeroy20vt]

could it be just rings if so could i put new ones in or will other work have to be done

[danny_p]

if the engine has been sat long enough the rings can stick, 

sometimes it's possibel to free them by putting siesel int he cylinders and letting them soak for a bit but your best off lifting the head  dropping sump then it's only a few bolts and you can pop the pistons out.   glaze bust the bores and refit pistons with new rings 

( yup it is easyet to say than do )

if you do find a phucked piston it's not the end of world tho,  got a box of random assorted pistons in the shed

[leeroy20vt]

cheers danny_p
when u say a wet and dry test wat do u mean m8
i will do a comp test tomoz

[l333]

hi dry compression check is remove plug and wang it over with throttle open best to isolate fuel supply first. wet is the same but with a bit of oil in the bore to help seal the rings. if you get a big difference between wet and dry then you no its prob rings but compression check dosent normly show an oil control ring fault

smoke on startup = seals.   smoke when  reved / loaded normaly  = metal

but as said this should give you a good indication as to the smoking

[DarnPB]

If the car has been sat for a number of years, then what are you going to expect? I would get both carbs running properly, then run it hard and get the loose carbon out of the system. Carbon bakes onto the components such as exhaust ports in the cylinder head, the valves and the pistons. But the carbon will soften up and become flakey and burn off with use. This will be the cause of your smoke.
If you think the rings are stuck in their grooves then try, as said before, pouring a little diesel into the bores or some brake fluid and leave to soak over night, then again, run the engine hard and get some heat into it.

[leeroy20vt]

cheers guys when u say a little deisel or brake fluid would u say a cap full down each bore will do the trick
thanks again i hope its nout major