Need info on trouble shooting my project 89 745 Turbo.

RCR · Post by **RCR** » 25 Apr 2011, 09:47

Defective OEM plug has wounded my 98 V90 so I need to get this one up and running ASAP.
I drug this one home last fall and it has been just sitting for the last 7 years.
It was an attempted theft off a local lot and the balancer was already dead so the elderly owner just wrote it off on the insurance first and then his taxes, pushed it to the side and let it sit. I wound up with it when he contacted me about selling the lot (I'm a Realtor) and I saw it on the back of his lot.
So far I have straightened out the minor wiring issue (stuff just unplugged nothing cut) + replaced the fuel pump relay and now have power to the fuse for both pumps but both pumps seem to be dead. The tank was bone dry so the rear pump is certain to be toast along with the filter sock and likely so is the under car from everything drying up inside. I have a new in tank pump sock and filter on hand and will start working on her later today. She turns over nicely has good compression across the board and good spark. I want to fire it if possible before I pull the balancer and do the full timing set. The belt that is on it looks good enough to safely try and start it.
First I have 2 manuals for this car but both have nothing outside of very basic info on the fuel system in them.
I need a link to some info on the BOSH system in this one so I can start working toward trouble shooting it.
I also need to know how to access the in tank pump on the wagon.
Suddenly I'm REALLY motivated on getting the old girl running!!
I until I bought the V90 4 years ago had never even ridden in a Volvo much less worked on one. All my experience with doing my own work has mostly been on old muscle cars. I am lost on trouble shooting the electronics so any help would be appreciated. I do have a background in Electronics (military)just not automotive.
Here is the 740

Check out the odometer an 89 with only 130K actual miles! Every service interval up to 128K was stamped in the manual by the dealer!

The BIG TIME dead balancer!

I need reliable transport with the V90 down and have big time motivation on this one as of now!
Plans were to get her fired this Spring then do a full on IDP suspension and later build a squirter block 8 valve with a big turbo. Now it just get it back running at close to tune O for a DD till I can get the V90 running.

Post by **jimmy57** » 25 Apr 2011, 12:01

the in-tank pump is accessible through a cover below the forward floor panel just behind the back seat. You have to unbolt it via the bolts at its rear edge. The square cover will then be revealed.
The main pump is under the car on driver's side just about the back edge of driver's door.

RCR · Post by **RCR** » 25 Apr 2011, 13:01

jimmy57 wrote:the in-tank pump is accessible through a cover below the forward floor panel just behind the back seat. You have to unbolt it via the bolts at its rear edge. The square cover will then be revealed.
The main pump is under the car on driver's side just about the back edge of driver's door.

Got the cover open and the bung nut loose having trouble getting all the lines loose at this point.

bugeye58 · Post by **bugeye58** » 26 Apr 2011, 01:30

That's a nice looking wagon. i wish the interior in mine was that nice. Yours even seems to have a headliner!
I recently had to replace the entire in tank module on mine, due to the pipes rusting through, so here's a tip. Before removing the module to access the pump, mark the module position relative to the tank opening, and remember how you have to turn it to get it out. It'll make re-installation a lot easier, and ensure that your fuel gauge reads correctly.