Katmandu

They other day I went to start my 98 12 Valve after it has been sitting for (2) days.

I took a good minute or two of cranking to finally fire the beast up. Once started, it sputtered for a few seconds and then cleared up.

It's started fine every since (hasn't sat for more than 2 days either).

What could of happened here ??

waldersha

Probably have an air leak somewhere. I would check your return fuel hose and the harness for the fuel preheater. Those are the most suspect places. The fuel hoses deteriorate and will leak air in without necessarily leaking fuel out.

Do a search about air in lines. Tell you everything you ever wanted to know.

Bobcat698

Any fuel leaking under the truck?

Katmandu

It does have a leak, but can't really tell if it's oil or diesel.

It's coming from the area of the 2nd to last valve cover from the rear. Not sure if it's the valve cover gasket for that particular cylinder or maybe a fuel line. I guess I got investigate that area a little deeper then.

somis13

the leak your describing sounds like the return line. its in that area, real close to the block, and very hard to follow, and prone to cracking after 8 years or so. mine did the same.

Reelay

My 95 was hard to start after sitting over night. Had to crank on the starter several times after "wait to start" light went out. Checked all the suggested trouble shooting processes, such as relays, recrimp relay wires, heater grids, ect. What I found was a loose fuel filter, I must not of tightened it enough and was loosing pressure over night but that filter was installed several months back. Evidently it worked itself loose. Hope this helps someone else out.---------Ray

manjerovic

I used to have this problem about every 6 months when I lived in HOT Texas and about every 2 years now that I live in cooler PA. The return line from the injection pump since it runs on top of the engine gets too hot and will develop pin holes which will break the vacuum on intake side of the injection pump. To start the truck you have to prime the lift pump if the truck sits for a 2 or more days.

Easy test to see if this is the problem....Park your truck on a hill (doesn't need to be steep maybe 1 foot grade over the length of the truck) with the engine on the down hill side. If your truck starts after a few days without having to prime it, then splice in a section of return line from the injection pump down past the engine to about the firewall.

Now I've heard alot of stuff about the marine grade hose working best. But it is expensive and there aren't a lot of boat supply places in western PA. So the last time I fixed this on my truck, I put the regular fuel hose (5/16?) inside a section of heater hose. The heater hose seems to keep the direct heat off of the return line and I haven't had a hard start in a few years.

Good Luck