Club 80-90 Forums

So...anyone replaced piston rings without honing the bores?
The engine has done 50,000miles since a complete overhaul/rebuild, the top ring and the oil control are worn out [1.6mm ring gap!!] the second ring is as new [.45mm ring gap].
What does the panel think?
Ta.

honing should be done to remove glaze from bores
at 50,000 there won't be any glaze

dave friday wrote:The engine has done 50,000miles since a complete overhaul/rebuild, the top ring and the oil control are worn out [1.6mm ring gap!!] the second ring is as new [.45mm ring gap].
What does the panel think?

I think whoever did the "complete overhaul" "forgot" at least one something. I wonder how much else they "forgot"?

AdrianC wrote:

dave friday wrote:The engine has done 50,000miles since a complete overhaul/rebuild, the top ring and the oil control are worn out [1.6mm ring gap!!] the second ring is as new [.45mm ring gap].
What does the panel think?

I think whoever did the "complete overhaul" "forgot" at least one something. I wonder how much else they "forgot"?

Hello,

Sounds like....

New set of rings all round....

Glaze busting.. (in his best blue peter voice).. you will need some 600 grit emery paper, a 'letter' sized sponge, some squezy washing liquid..

and a responsible adult...

wet the inside of the bore with washing up liquid, mount paper on flexy sponge, and sand DIAGONALLY, both ways.. wash, rinse and dry, coat with oil..

Voila!

Cordialement,

Thanks both,Adrian what do you think was forgotten? the block was bored to 77.51mm and 77.48mm pistons and rings fitted,new bearings fitted,new oil pump,new cylinder head...all the fitting was done by me.

Thanks Sarran,I have a new set of top quality rings [bought at great expence here in Spain ] and am waiting on a hone and stretch bigend bolts.

dave friday wrote:Thanks both,Adrian what do you think was forgotten?

I was assuming it was built by somebody else, and they'd "forgotten" to fit new rings. But if you built it, and it was rebored and new pistons/rings, then that can be ruled out...