Re: help me revive this beast (Yanmar 4JHE on F39PH)
Posted: Sun Jul 12, 2015 9:00 pm
OK
back at the boat
loosened the 3 nuts that secure the injection pump (not easy)
with hard pipes attached to injectors and pump, there is very little play - pipes are simply too hard - don't flex, bend, or give
with pipes *detached* at the injectors, there is major rom for adjustment - at least 5° of rotation, maybe more
seems like the pump is designed to be timed statically with pipes detached - i.e. at 12°bTDC, injector #1 opens
then pump is tightened securely, *then* pipes are reattached
but I cannot get them to 'stretch' hardly at all to accommodate a significantly different timing setting
(with the pipes attached, but nuts loose, I can 'wedge' the IP a little more advanced, and it seems to run a little better, if I use my imagination
but I am making almost no difference to the timing
good news is, this is definitely how the timing is supposed to be adjusted
do I need a new set of pipes? is there more play when they are new? are there different size pipe sets? can they be bent or elongated on a bench?
I may need as much as an extra 1" of pipe
thanks for any thoughts
Rolf in MA
back at the boat
loosened the 3 nuts that secure the injection pump (not easy)
with hard pipes attached to injectors and pump, there is very little play - pipes are simply too hard - don't flex, bend, or give
with pipes *detached* at the injectors, there is major rom for adjustment - at least 5° of rotation, maybe more
seems like the pump is designed to be timed statically with pipes detached - i.e. at 12°bTDC, injector #1 opens
then pump is tightened securely, *then* pipes are reattached
but I cannot get them to 'stretch' hardly at all to accommodate a significantly different timing setting
(with the pipes attached, but nuts loose, I can 'wedge' the IP a little more advanced, and it seems to run a little better, if I use my imagination
but I am making almost no difference to the timing
good news is, this is definitely how the timing is supposed to be adjusted
do I need a new set of pipes? is there more play when they are new? are there different size pipe sets? can they be bent or elongated on a bench?
I may need as much as an extra 1" of pipe
thanks for any thoughts
Rolf in MA