escort cvh 1.4 running on 3 cylinders
richardh - 3/8/12 at 07:59 AM
Hi, ive just completed a compression test and found that one of the cylinders is pushing out sod all.
i tried putting some oil down it and no change.
as i use this engine for autograss racing, its now an ideal time to do some minor mods to get more oomph.
trouble is i don't know what can be done to these things cheaply.
i guess honed out inlet and exhaust ports, different cam, different tappets, piston liners, new shells?
Don't want to spend the earth as theres only a few races left and i'm looking to go rear wheel next year.
so i need the basics to get it to be speedy enough to attract someone to be interested in it.
(personally i say that the slower you go gives more time for people to read your advertising stickers anyway) 
Any ideas, links etc are very welcome chaps/chapesses
Alan M - 3/8/12 at 08:03 AM
quote:
Originally posted by richardh
Hi, ive just completed a compression test and found that one of the cylinders is pushing out sod all.
i tried putting some oil down it and no change.
as i use this engine for autograss racing, its now an ideal time to do some minor mods to get more oomph.
trouble is i don't know what can be done to these things cheaply.
i guess honed out inlet and exhaust ports, different cam, different tappets, piston liners, new shells?
Don't want to spend the earth as theres only a few races left and i'm looking to go rear wheel next year.
so i need the basics to get it to be speedy enough to attract someone to be interested in it.
(personally i say that the slower you go gives more time for people to read your advertising stickers anyway)
Any ideas, links etc are very welcome chaps/chapesses
Is the oil getting to the top end ok? I know if these engines are run low on oil they will drop a cyclinder or two as the hydraulic tappets run dry
richardh - 3/8/12 at 08:07 AM
they look wet enough but i'll check that
thanks
britishtrident - 3/8/12 at 02:43 PM
Bent valve
richardh - 3/8/12 at 02:45 PM
might be
trouble is having to take it apart to find out and then i might as well uprate it all with something
theres not much you can do with a cvh 8v
britishtrident - 3/8/12 at 02:52 PM
10 minutes doing a cylinder leak-down test would tell, not exactly a major strip-down anyway to switch the head.
richardh - 3/8/12 at 02:55 PM
oh, can't recall how to do that.
think i might have done one about 6yrs ago but not sure
britishtrident - 3/8/12 at 02:57 PM
quote:
Originally posted by Alan M
quote:
Originally posted by richardh
Hi, ive just completed a compression test and found that one of the cylinders is pushing out sod all.
i tried putting some oil down it and no change.
as i use this engine for autograss racing, its now an ideal time to do some minor mods to get more oomph.
trouble is i don't know what can be done to these things cheaply.
i guess honed out inlet and exhaust ports, different cam, different tappets, piston liners, new shells?
Don't want to spend the earth as theres only a few races left and i'm looking to go rear wheel next year.
so i need the basics to get it to be speedy enough to attract someone to be interested in it.
(personally i say that the slower you go gives more time for people to read your advertising stickers anyway)
Any ideas, links etc are very welcome chaps/chapesses
Is the oil getting to the top end ok? I know if these engines are run low on oil they will drop a cyclinder or two as the hydraulic tappets run dry
The tappets pump up rather than run dry, if the oil in the sump is too thick oil gets pumped into the hydraulic tappets quicker than it can
leak back out so they jack up, that shouldn't effect a compression test.
Alan M - 3/8/12 at 04:30 PM
The tappets pump up rather than run dry, if the oil in the sump is too thick oil gets pumped into the hydraulic tappets quicker than it can
leak back out so they jack up, that shouldn't effect a compression test.
Wouldn't that lead to valves being held open?
britishtrident - 3/8/12 at 07:22 PM
quote:
Originally posted by Alan M
The tappets pump up rather than run dry, if the oil in the sump is too thick oil gets pumped into the hydraulic tappets quicker than it can
leak back out so they jack up, that shouldn't effect a compression test.
Wouldn't that lead to valves being held open?
It is all to do with leak down rate, not really a problem a cranking speed so it isn't going to show up in compression test, The problem
would arise after a cold start, gun the engine when the oil is cold and as revs rise the oil won't leak out fast enough.
10w40 oil is pretty essential in these engines, I would use 5w/40 or for urban road use even 5w/30.