Well I replaced my fuel pump about a year ago with a Napa unit. About 6 months after that it started giving me a hard time starting due to it loosing the prime. The check valve that keeps fuel pressure inside the line for a fast start was failing and letting the pressure drain back into the tank. So for all this time I would crank the ignition to start 2 times before I try to start to prime up the pump. Sometimes I would flood the engine by priming it too much.

I did a good search online and there was a common fix using a BMW check valve kit. Now no longer made. Finally I found a simple but perfect check valve on Ebay. On 93-down there is an external filter where there is a small section of rubber fuel line which is 5/16. I just cut the line and installed the valve with new fuel line in between.

So far I only had it installed for 1/2 a day but normally it would drain back by then, but with this installed it started perfect every time. Easy fix!!

Here is the link. (This type of check valve may help with delayed engagement on autos due to bad or no check valve)
http://www.ebay.com/itm/5-16-Check-V...#ht_599wt_1185


Here are a few pictures.

Check valve


Check valve installed behind the fuel filter. (I just hosed off the Gas that leaked during the install, that is the wetness you can see in the photo.)

 

Well as an update, after sitting over night several times it holds. Now it starts up right away EVERY time. Easy simple fix for those who have a hard start due to loosing fuel pressure.

 

cool good to know

 

Did you install it before the fuel filter or the looped hose past the fuel filter on the tank side ?

 

If I had to hazard a guess, I would suspect that as close to the tank as you can get would be best.

 

Aye, HeyYou has it right. But the inlet to the fuel filter would be good enough for most people.

RwP

 

I installed mine right before the fuel filter as that was the only rubber line accessible. Here are the photos that should have been in that first post.

 

I'd go back and put fuel injector hose clamps on there. Or at least a second clamp each location, turned 180* out.

RwP

 

Mine is a 1989 with 133,000 miles . Had to crank along time to get it to start . I finally figured out if I cycle the key 3 times until I here the pump stop running it will start right up and run well . I ordered the same check valve . My fuel filter design is a little different. It would be easier to put it ahead of the fuel filter , but mine has a short looped hose on the inlet of the fuel filter . With a 90 degree fitting I think I could put it there . I can't see if would make any difference ? I suppose the closer to the tank , the more fuel in the line. Keeping the fuel filter full would help with that effort . Makes sense .

 

​​​​​​The closer to the tank , less fuel to drain back . Makes sense the more fuel you can keep in the line , the better it will start . Keeping the fuel filter full I think would help . Thoughts ?