blow by

[scruff123]

how much blow by is normal? and what is normaly rong with the engine if it is excessive?
myn seems to have a fair bit

P7292886.JPG

is this the norm? or to much?

cheers

[turnturn]

That seems a lot to me Scruff123.

[wbski007]

Seams like alot to me also, but then again I have no idea how much these Isuzu's produce either, If you have a catch can and the motor is'nt useing oil I wouldn't worry about it to much, I've had big diesels like Detroits and Cats that had alot of blowby but its normal for them, as for Isuzu's I don't know?

[geeves]

Thats nearly as bad as a pajero I test drove a while ago. (It had a pto winch) The breather hose on that actually whistled it was so bad. I found some convenient rust that saved me from having to make an offer he was bound to refuse.
Generally I would say bad rings but new good oil might also help. My bighorn would fume not much less than that when useing repco oil and it was near the end of its change life but the dello300 stopped that completely but caused leaks and the valvolene has been acceptable ever since.
What mileage has it done and how regular are its oil changes from new

[steveNZ]

Hi scruff
the Lucas Heavy Duty oil stabilizer seems to have helped reduce the blow by ive been getting so might be worth a try

[scruff123]

Thats nearly as bad as a pajero I test drove a while ago. (It had a pto winch) The breather hose on that actually whistled it was so bad. I found some convenient rust that saved me from having to make an offer he was bound to refuse.
Generally I would say bad rings but new good oil might also help. My bighorn would fume not much less than that when useing repco oil and it was near the end of its change life but the dello300 stopped that completely but caused leaks and the valvolene has been acceptable ever since.
What mileage has it done and how regular are its oil changes from new

engine has had new pistons and liners 60000ks ago and has had 5000 k or less oil change intervals, was running high qaulity petro canada 15-40 and cant sourse that so running valvoline super diesel for the last 2 oil changes, the pipe does whistle slitely with amount of fumes coming out.

hope it not the rings, if it is whats the prosess of changing them? and how much roughly for a mechy to do it?

[geeves]

New pistons and liners and only 60000km shouldnt do that. Are they genuine with chrome liners and iron rings or are they aftermarket iron liners and chrome rings?
The genuine liners can be difficult to bed in. A mechanic might have a trick or 2 that might help

[scruff123]

thats what i thought, im not 100percent sure but i think they are chrome liners and iron rings, ill have to ask the previous owner, hes a mechanic and did it himself before i brought it. mite try a differnt oil and some of that lucus oil stabiliser that stevenz recomended, and change my catch can as that wasnt working and sending oil everywere

[geeves]

A few people have had problems when fitting chrome liners. In a normal engine the liners are honed after fitting which gives an even finish and removes any effects from block warp-age. Cant do this on a chrome liner

[scruff123]

the engine seems to run sweet and has plenty of power, it doesent like starting hot tho, like it wont fire up, feels like a fuel problem tho???? or would low compression from bad ring cause that?

[geeves]

low compression will do that.

[scruff123]

what causes low compresion?

[steveNZ]

Low compression is normally caused by the rings being worn out broken or not having bedded in properly and can also be caused by a valve or vales not seating properly
There are some special oils available that are designed for running in new and reconditioned engines they allow the rings to bed in better.
Cummins diesel and some other sites recommend a running in oil on all new and reconditioned engines saying that if the oil is to good it doesn't allow the rings to bed in properly

Might be worth doing a google on it and try one at next oil change
60000k is a lot for not bedded but if too good a oil was used from the start it might be worth a try for the sake of a oil change

http://www.pennzoil.co.nz/products/moto ... il_run.asp
just one product many more out there

[scruff123]

ive run powerup (www.powerupnz.co.nz) oil additive in it since i got it wich wouldnt let it bed in at all as it put a strong lubrecating coating on everything, i mite try a bedding in oil, how many ks should it take?
cheers for al the info fellas

[steveNZ]

100 hours running time according to Cummins that's 10000km at a 100 kph
so i would go about 5000km standard time for a change but it could be different from one oil to the other so have a good read of the makers recommendations.
The pennzoil might not be the best one just Google running in oils and there's lots of different ones available
If you have been running powerup right from the time of rebuild would make sense the rings never got to bed in properly
Im thinking of trying it in mine next oil change might help um re-bed a bit cant do any harm