Hey guys,

I've spent the last two days going through posts on injectors. I got close once to what I thought might help my dilemma. Bought this boat 3 seasons ago, engine in a basket, no injectors. Tried GM's stock injectors for automotive(19lb/hr), didn't run. Asked around, an injector shop recommended 22lb/hr. Ran o.k., not great. The post here suggested it might be around 26lbs/hr. Volvo part # is 3857700, can not find what the lb/hr is on these. Purchased injectors off 2000 Merc 7.4L part # 25180245. Still hesitates, although not as badly, on throttle. These are 24lb/hr. Does anyone have the volvo injector and/or know what the lb/hr is supposed to be? 2000 7.4L Gi 310hp.

Did the engine have a or the right fuel pressure regulator needed to match the injectors? What fuel psi are you getting?

It didn't, had to buy the "whole" fuel pump system new. The low side is 18psi and the high around 40psi. What looks like a fuel pressure regulator is "inline" back by the distributor.

I believe 18 psi on the low pump is to hi, should be around 7-8 psi. The regulator should have a vacuum line hose going to it and when you pull the hose off the psi should go up normaly 4-6 psi to the hi side of the pump. Sorry I can't help you with the injector size. But there is a few guys here that might be able to get you close to what you need, And if not you could call volvo your self they should be able to help. Good luck with it.

Fuel pressure should be definitive #, so I'll try to check that out. It would be nice to know what the injector size is to at least eliminate that question mark. I suppose I could drop $1600 to erase it, but that's why I'm on this forum..:-) BTW, thanks for your input.

have you tried the people @ www.injector.com

Will try first thing in the AM, thanks for the tip..

Called injector.com, won't give out the specs, same old story, two years later. Did talk with a mechanic that pretty much assured me that all 2000 7.4L engines from GM were equipped with the same basic parts, including the injectors and that I should be o.k. He also said the injectors from the VP would have the same Rochester # on it and not the VP part #. So..., off to get these Rochester/Mercruiser/VP injectors cleaned and flow tested. I WILL post the lb/hr!

Finding are in. Although I realize that most who visit this forum are not too interested in stock equipment, this would be info for someone who happens to come to this site for the reasons I did. Doing a search on the Rochester # off an original GM 7.4L mpi 310hp marine engine, the flow test supported the #'s from injectorrx website. 24.2lb/hr @ 42 psi. Hope this info helps someone else trying to find a stock injector without spending $200/injector!

hi
is there any update for a replacement injector for the 7.4 other than the original 200 usd/injector...

any suggestion appreciated...
thanks