88 F250 7.3 Engine Surges

[Old Goat]

Last night I did a lot of searching on Google reading about 6.9/7.3 IDI
engine surging. There is a ton of Threads on this problem.

I came up with several solutions to what causes this.
Fuel Lift Pump, not enough fuel pressure from Filter to IP.
Should be 4 -6 lbs. Install a Fuel pressure gauge from Filter to IP.
Could also be problem with IP wore out, stuck metering valve to Governor.
Also sucking in air some where.

A friend of mine was hauling his car from here in Nevada to South Dakota,
some where along the trip broke the Vacuum Belt or the Alternator belt,
and one took out the other. After replacing them he started to have this
surging problem. Engine ran good up till this problem.
Said it would surge from 500 to 1500 or so RPM`s, at an idle would die,
but driving it would run ok. Did some adjustment on the pump and said
the surging dropped some.

Don`t know the miles on the engine, but last Wed evening when he was
here at the house, it was smoking pretty good idling. Truck look pretty
well used, Iam thinking time for Pump and Injector replacement and timing.

This past week I was at PNP and pulled a IP and Injectors off a 89 7.3.
I was amazed at how clean the Injectors were except for the 2 center
one`s on driver side. Thought maybe this engine might have a leaky head
Gasket why it was in there???

I was thinking my friend if tight with money, I could send him the pump
and Injectors if it would help him...it would be a crap shoot.

So whadaya Xsperts thnk?

Goat

 

[Cubey]

Maybe when the belts went, they damaged the soft or hard line down at the lift pump? It's right down under the alternator and vac pump. And maybe it was just a weird coincidence that the belts went right before the lift pump started to die.

Lift pumps are pretty cheap (~$30) and not TOO bad to change on pickups. Vans are worse due to the radiator and such being much closer. Replace the soft line down there while you're at it. It's a short piece of 3/8" fuel hose.

 

[IDIBRONCO]

Don`t know the miles on the engine, but last Wed evening when he was
here at the house, it was smoking pretty good idling. Truck look pretty
well used, Iam thinking time for Pump and Injector replacement and timing.

I would have the timing set before replacing any components. This sounds like the timing's retarded to me.

 

[Old Goat]

I talked to him yesterday, and he said he threw a can of Sea Foam in the Fuel Tank and ran it. Seemed to clean up most of the surging. Waiting to her from him.


Goat