BUP

That link is to the Mercruiser install but the adaptor harness is the same that Volvo uses -

The link you posted - in the pic for the small block there is a coil driver again do you have this with your Volvo. I could be wrong as I am thinking possible Volvo did not use it because different ignition set up I can not remember that part of it and might be confusing it with the Mercruiser install. The ground wire needs to be all by itself as it shows for the install of the big block in the link you posted.

If anyone can FIND & post the INSTRUCTIONS for the MEFI 3 conversion to MEFI 4 - TBI - VOLVO again it has to be the VOLVO instructions and for TBI EF model. This might find the problem to fix this pig once and for all. Someone that is good on the net might be able to find the instruction sheet for this. Again it needs to be for the VOLVO not Mercruiser.

Possible call Volvo and have them email it to you and then post it good luck.

nunnink23

I will scour the Internet tonight. But we may have found the problem anyway. I don't have the y harness connected to the cool fuel pump harness as the instructions state. I have it off the boat a matter of fact because I didnt know where the heck it went, and it seemed like it was unused. I'm going to map the wires back to the ecm tonight and follow those instructions, then figure out if the y cable simply ties into the ground circuit from the fuel pump, or if it ties in to the 12v supply to the pump. It could be either way. I will post detailed info about it, and what pin on the ecm it connects to. I may not be able to start it however, because I have to get drop the oil pan slightly and put a new timing cover on. IM hoping to do this without pulling the engine. The oil pan should flex a bit if I take 4 bolts out I think.

BUP

Hopefully my post # 433 can help you with all the connections.

I hope as I really tried to remember the connections and set up. The coil driver is throwing me off because I know Mercruiser small blocks use it but again POSSIBLE VOLVO does NOT. NOT 100 % sure about that one. Like I already mentioned.

I did tell you to run the harness down to the fuel pump and figure out the connections with the plug ins so hopefully you can get it right.

Again find this VOLVO instructions or call Volvo for them. The ground wire for this conversion I BELIEVE needs to be all by itself as well. Look at how they installed on the big blocks in the link you posted - there is a reason for this.

28Eliminator

The oil pan? You need to loosen all of the side bolts on the pan to get the timing cover on without screwing it up. they don't all need removed, but definitely need loosened. broke one a couple of years ago trying to short cut that process helping a friend change cams. Spent 20-30 more minutes loosening the bolts and the new cover went right on.

nunnink23

Do you think that will disturb the rtv on the back of the rear main housing? I was trying to keep that in tact and just bend the front down slightly.

28Eliminator

We never messed with the rear other than maybe loosening the bolts and it has never leaked. I know we loosened all of the side bolts and probably removed the front 5-6 on each side. Then we made sure everything was clean of oil and rtv'ed the joints/90's.

nunnink23

Okay sounds good to me

SB

I found a 'snipit' on the net that stated Merc engines using MEFI 3 with the Thunderbolt ignition uses a seperate injector driver. MEFI 3 with EST ignition does not.

It was somehwer in here: http://boatinfo.no/ but I can no longer get my computer to work with that site. Doh.

nunnink23

Well maybe my discovery doesn't matter then. Maybe that was used for a Merc app.

BUP

Yes I remember it now and posted why I thought so in post # 441 second paragragh. Just was not sure about it. Another reason I asked OP if he has the coil driver and ??? that - the bracket ??? and plug in for it.??? - I did not think so but and its the but you have to worry about. I hate not being 100 % about things.

The best to do is find the VOLVO instructions to correctly adapt the MEFI 4 and all the connections properly. You have been all over the planet with this thing so do not wing this - find the instructions and do it right. Time to stop winging it trying to make this engine run correctly and put back together correctly to say the least. it has not worked from start to currently. Just saying.