oldharry
Well-Known Member
Re: T90 - BC 1.5 engine problems, advice please.....
I agree with Joe, having had several of these excellent engines over the years: theres a problem with the rings. If the engine had been badly neglected - sludgy oil etc - I would expect to find them well gummed up, and probably sticking. That would cause the blow by (chuffing at the oil filler). Or they have got so fouled that they have been snatching and have broken, but I think thats less likely as 3 out 4 cylinders are affected. Glazing is not a likely problem. Also unless it has been very heavily used and abused I think worn bores are unlikely.
Certainly well worth having the pistons out, cleaning up the grooves and fitting a new set before writing off the block altogether. The old ones may still have plenty of life left once freed off. Check the ring gaps before investing!
All the other symptoms you describe are attributable to the low compression stuck rings would cause.
And getting rid of white smoke? First is it really smoke, or is it steam from an over hot exhaust? If so then there is insufficient water cooling the exhaust and it is boiling off - not good if you have a flexible rubber exhaust pipe as it may damage it. If it really is white smoke, a bit on start up and clearing within 30 seconds is nothing to worry about - many older engines do that. If it is excessive on cold start, check the cold start pre-heat system. If it continues after the engine has warmed up then it is basically a combustion problem - it is actually diesel 'fog' which is unburned fuel passing through the engine and out of the exhaust. Causes: low compression causing incomplete combustion; injector faults; insufficient fuel to the injectors (pump fault); check injection timing; leaky or incorrectly set or timed valve gear.
Note too that an exhaust system which is contaminated with fuel from excessive cranking will also give off white smoke while the excess fuel dries out.
Oh, and re the water temp reading Dick: you will not be able to put your finger in water that is much over 55 - 60c without a marked verbal reaction that is likely to get you in trouble with SWMBO! /forums/images/graemlins/crazy.gif
I agree with Joe, having had several of these excellent engines over the years: theres a problem with the rings. If the engine had been badly neglected - sludgy oil etc - I would expect to find them well gummed up, and probably sticking. That would cause the blow by (chuffing at the oil filler). Or they have got so fouled that they have been snatching and have broken, but I think thats less likely as 3 out 4 cylinders are affected. Glazing is not a likely problem. Also unless it has been very heavily used and abused I think worn bores are unlikely.
Certainly well worth having the pistons out, cleaning up the grooves and fitting a new set before writing off the block altogether. The old ones may still have plenty of life left once freed off. Check the ring gaps before investing!
All the other symptoms you describe are attributable to the low compression stuck rings would cause.
And getting rid of white smoke? First is it really smoke, or is it steam from an over hot exhaust? If so then there is insufficient water cooling the exhaust and it is boiling off - not good if you have a flexible rubber exhaust pipe as it may damage it. If it really is white smoke, a bit on start up and clearing within 30 seconds is nothing to worry about - many older engines do that. If it is excessive on cold start, check the cold start pre-heat system. If it continues after the engine has warmed up then it is basically a combustion problem - it is actually diesel 'fog' which is unburned fuel passing through the engine and out of the exhaust. Causes: low compression causing incomplete combustion; injector faults; insufficient fuel to the injectors (pump fault); check injection timing; leaky or incorrectly set or timed valve gear.
Note too that an exhaust system which is contaminated with fuel from excessive cranking will also give off white smoke while the excess fuel dries out.
Oh, and re the water temp reading Dick: you will not be able to put your finger in water that is much over 55 - 60c without a marked verbal reaction that is likely to get you in trouble with SWMBO! /forums/images/graemlins/crazy.gif
