Volvo L70 Hunting

[karlbradshaw]

Hi, I've got an early L70 loader. It's starting to hunt a bit during lifting, OK when not under load.

It's also occasionally cutting out when returning to idle after being worked. Doesn't seem to do it when stationary and playing with throttle, more when moving and returning to neutral. Am assuming fuel related, have changed filters etc, is there anything else on these, like a gauze in the pump that might need cleaning. It's got a TD45B in it.

 

[funwithfuel]

What is your warm idle speed? Should be 600-625. You may need to bump your idle set screw.
Do you have the often neglected slurry bowl? It's a glass bowl sediment strainer. The seals often dry up and crack. This allows air in the fuel. This will make for hard startd in the morning. Next to that, there is the suction line from tank to slurry, it collapses internally. This usually shows up as inability to reach full throttle and hard starting.
I'm sure thepumpguysc will be along shortly to fill in the things I forgot.

 

[karlbradshaw]

Hi, thank you for your reply. I think it has the bowl but appears to be disconnected so the tank feed goes straight to the pump.

 

[funwithfuel]

Oh no. That's bad. God only knows what your lift pump has suffered through. I'd make every effort to get something to protect that lift pump.
After that, let's see how everything goes. Please keep us updated on your progress

 

[karlbradshaw]

I think I'll try and get a new bowl (or maybe take the old one out and clean), clear line from fuel filters to tank with compressed air, then try and put back together again.

 

[karlbradshaw]

Would the fuel filters not take most of the crap out?

 

[funwithfuel]

After the trash went through the lift pump, yes. That slurry bowl is your only protection for the lift pump against water and debris

 

[karlbradshaw]

Right, lets get cleaning.....

 

[karlbradshaw]

Have ordered a lift pump. Any top tip on bleeding this on your own. Got fuel at filters but not firing, can't crank and bleed injectors at same time

 

[funwithfuel]

Run you a couple jumper wires from the starter to a button. You control the crank.

 

[karlbradshaw]

Cannot get it running. Wired a switch up so I can bleed it. I've got fuel at the lift pump, up to the filters and into the injector pump, just cannot get the fuel through when cracking off the injectors. Batteries on charge now. Any tips?

 

[funwithfuel]

Is your shut off cable all the way in?

 

[funwithfuel]

It ran before. Did you reseal the slurry bowl with all new o rings, including the screw that holds it all together? Do you have any way of gauging the fuel pressure in the pump, even if you can use a bleed port on top of the filter head. We need to know if your maintaining lift pump pressure inside the pump.

 

[funwithfuel]

Do you have a fuel line that runs around the other side to the intake manifold?

 

[thepumpguysc]

Loosen ALL the steel lines AT the injectors.. Use the hand primer on the supply pump until u hear fuel flowing thru the overflow valve going back to the fuel tank.. Now crank the engine until fuel squirts out the loosened lines at the injectors & retighten.. it should start now.

 

[funwithfuel]

Loosen ALL the steel lines AT the injectors.. Use the hand primer on the supply pump until u hear fuel flowing thru the overflow valve going back to the fuel tank.. Now crank the engine until fuel squirts out the loosened lines at the injectors & retighten.. it should start now.

It's about time!

 

[karlbradshaw]

Hi guys, thank you so much for your help. I'm struggling here, appreciate your effort.

The slurry bowl is still disconnected as I haven't got the fuel pipes made up yet. The tank feed line is clear, it goes to the lift pump. The line then comes out of the lift pump to the fuel filters. The line then drops to the injector pump. At this point the lift pump is priming and fuel is coming out for the connection into the injector pump, but there is still no fuel at the injector pump / injector pipe unions. Hand priming or cranking, there's nothing. I don't know what I've missed. To me the lift pump should be OK as it seems to be priming to the injector pump. If it was weak would that stop it coming at injector pipes?

 

[karlbradshaw]

I have some videos of it if anyone has a whatsapp number I can send to?

 

[funwithfuel]

Have you checked your shut off cable, is it all the way in?
Have you disconnected the return line from the injection pump to see if your overflow is holding any pressure?

 

[karlbradshaw]

Right OK, guys, I'm sorry....