Truck keeps losing it's prime

[Tinstar]

The new filter bases have that hole completely removed.
If you can find one.
They are hard to find now.

The plug and seal modification seems to work very well, so I've read.

 

[corvette9]

i'll tap the hole for a pipe plug on Sat. I'll report back after testing.

Thanks BG

 

[cucvrus]

https://www.facebook.com/chauffeursnieuws/videos/1895616680721215/

Sound the trumpets I think you are on to something.

 

[scottladdy]

Those videos AND shoes made the wait to read this thread well worth it!

So, before I had figured out that the spin on conversion was ideal, I had the same filter base issue on both my trucks. Somewhere in the old posts is a source for the updated pressure sensor. I purchased these from a vendor in California if I am not mistaken. They were an easy fix and have held up for several years. HOWEVER, if I had it to do over again I would (and will) change to the spin on filters.

 

[MarcusOReallyus]

The shoes are still wrong.

 

[corvette9]

I took the filter base off Dude today. Removed the sensor, tapped the hole and sealed it with a bolt and permatex liquid metal. I have it parked back on level ground, now I wait till morning and see if it starts. Pluging the sensor hole took about one hour start to finish and cost nothing. Well worth a shot.

I'll report back Sunday morning.
BG

 

[corvette9]

I can't believe the fix could be these easy. The truck started right up as it should this morning. I'm still not convinced so I will let it sit for a few days next week and try it again. When my brother gets back from his vacation I'll have him do the same thing to his truck.

Thanks once again to Cucvrus and all the others that help with these problems as they come up. I'v owned alot of trucks over the years, gas and diesel but never a Chevy with a 6.2. The more I learn about these the easier they seem to be. I'll report back next week one more time and tell everybody how it go's.

BG

 

[corvette9]

Ok.. The truck started right up when parked over night every time. Then I tried letting it sit for 48 hours. Started right up. Then 48.hours again. This morning no start. This is getting on nerves. Now I just installed a fuel check valve in the feed line. I put it under the cover on the rt side frame rail. Check valve is made for fuel so it should last. I don't like to mouse things and understand it is putting a band aid on the real problem but I want to see if this works.
The turck will sit till Monday. Then we will see what happens. I'll report back

BG

 

[Mainsail]

The hole you plugged in the filter body isn't the only place air can leak in.

 

[scottladdy]

Fuel isn't leaking out; air is leaking in.
...
Either way, get a spin-on fuel filter and the problem should go away.

This!

The pressure sensor is only one (the most common) point of failure on these filter bases. There are a couple of other parts that rely on small o-rings to seal. If they are not sealing perfectly you could still lose prime.

Sounds like your situation improved when you blocked off the fuel pressure port. Progress! Now, please do yourself a favor and install a spin on base with water collection bowl and fuel heater option (since it does get cold up here). Plenty of threads on how to do this. New lift pumps are also cheap insurance and you only have one left to do .

 

[cucvrus]

Did you vacuum test your repair/ I did one and it leaked. I pulled the screw out and re-tapped it I checked it with the vacuum pump and it held negative vacuum for an hour. Good enough. No problem ever since. I think you did say you changed the lift pump. Is it dry in that area? And the valley of the engine where the throttle shaft goes thru the injection pump. Is that area dry? I know it does not have to leak fluid but it may be damp. Dead giveaway.
https://youtu.be/S0Ghf5mxf5Y

 

[corvette9]

Update to last post. Recap, I replaced all the rubber lines except the one feed line that go's from the filter to the IP. That did not fix the problem. Then tried removing the sensor in the filter base and pluged the hole. Seamed to be ok for a few days then one morning no prime. Now I was looking at maybe it is the IP. I talked to the diesel mech. that works on my wreckers and he said to put a check valve in the feed line from the tank. So I did. $12.00 at Napa for a fuel check valve. Never even heard of one. I removed the shield on the rt rail where the rubber lines are and installed the check valve.
It started right up every time. I let the truck sit for this whole past week. I just went out to try it and it fired right up.

Yea I know it's not the right way to fix the problem but it's way cheaper than starting to replace major parts. My brothers 1008 will get the same thing. I'll report back if it fails but I don't see how it could.

BG

 

[cucvrus]

It gets my vote. That tells me it is loosing prime behind the check valve. Good job. Dude will be well again.

 

[corvette9]

He runs like a top . Just went and gave it a much needed bath.

 

[scottladdy]

That tells me it is loosing prime behind the check valve.

Agreed.

If I understand the location where you put the check valve in, there is only the solid fuel line bridging across the truck to the drivers side, rubber fuel line to the sending unit, and then the sending unit "behind" that check valve.

Did you check back there to see if there is any fuel wetting?

Sounds like there's a leak somewhere back there which is likely to get worse over time. Hate to say it, but while you are at it ... might as well at least replace the rubber lines to the sending unit, plus any rubber lines you didn't replace when you put the check valve in on the passenger side.

Better than a fuel leak.

 

[corvette9]

Agreed.

If I understand the location where you put the check valve in, there is only the solid fuel line bridging across the truck to the drivers side, rubber fuel line to the sending unit, and then the sending unit "behind" that check valve.

Did you check back there to see if there is any fuel wetting?

Sounds like there's a leak somewhere back there which is likely to get worse over time. Hate to say it, but while you are at it ... might as well at least replace the rubber lines to the sending unit, plus any rubber lines you didn't replace when you put the check valve in on the passenger side.

Better than a fuel leak.

Fuel line to the sending unit is new. They where done when I put the new tank in when I first got the truck. The only rubber line that has not been replaced is the feed line from the filter to the IP. For that I would have to remove the intake manifold.

 

[firefox]

If I remember right, there is a method of replacing that hose without removing the intake manifold. I suggest you search on here for the post.

 

[scottladdy]

The only rubber line that has not been replaced is the feed line from the filter to the IP.

Probably a good idea especially if the age of the hose is unknown. I have successfully done this without removing the intake myself.

However, if this was the source of your issue the check valve would not have worked. The root cause of your issue has to be between the check valve and the tank. The check valve is not fixing the root cause, and the root cause has to be a leak. A leak in a fuel line is just something I would not rest easy with as eventually it could lead to more serious issues.

Just my . This advice is free as you paid nothing for it.

 

[corvette9]

Probably a good idea especially if the age of the hose is unknown. I have successfully done this without removing the intake myself.

However, if this was the source of your issue the check valve would not have worked. The root cause of your issue has to be between the check valve and the tank. The check valve is not fixing the root cause, and the root cause has to be a leak. A leak in a fuel line is just something I would not rest easy with as eventually it could lead to more serious issues.

Just my . This advice is free as you paid nothing for it.

Makes me wonder if it could be the sending unit. The steel lines that go across the frame to the tank are dry plus I pulled the clamps that hold them in place to make sure they where not rusty. They checked out fine. The sending unit is the only part left. There are no leaks around the unit. You can clearly see it. Maybe inside the tank?

I'll do a search for how to change that feed line. I see no way to get the hose clamp.

 

[cucvrus]

Sit down and relax. Are you feeling energetic and relaxed?

Remove the entire cargo bed. Breath a sigh of relief. You have had this bed off before and it was just recently. It will come off with ease. Beats the pants off one that has not had the bed off in 30 years and was in the north east all them years. It does not have to have a wet spot. Just a pin hole to allow air to get in. Good luck. Dude likes you. He will make it easy on you. Report back. How about some pictures?