Thump on cold start?

Boyce604 · Jan 22, 2014

I replaced my moms lift pump in her 08 king ranch. So been driving it all week to see how it is. Yesterday was a high of 20. I came out of work and let the glow plugs cycle a few times and started. It made like 3-4 thumps out of what sounded like intake then stopped. Truck ran great and NO smoking or anything.

I got up this morning for work and was 18 degrees again. But no way to plug it in at home. So I started it same way, few glow plug cycles and did same thing. Bout 3-4 thumps and got quiet and sounded normal.

Is it just from bein cold. It's supposed to be 50 this weekend so imma let it sit till then. I'm just parinoid at stuff like that.

I know my 32v 5.4 has a lifter tick when cold and goes away.

Boyce604 · Jan 22, 2014

I came out of work today and was 37. Started truck and had 1-2 very faint thump and was normal again. I'm guessing it's just from bein cold?

webb06 · Jan 22, 2014

Sounds to me like a lifter is slightly collapsing when cold then the thick oil doesn't pump it back up until it warms up very slightly. Could be wrong but thumps through the intake are usually valve train related

Boyce604 · Jan 23, 2014

It's only bout 2-3 thumps, even on a cold start. I can shut off let sit 30 mins and didn't do it.

How do I check the lifters?

greasltn · Jan 23, 2014

Like webb said, sounds like lifter is collapsing when cold then pumping up when starting. The only way to get to the lifters is to take the heads off. If you blow the HG and rebuild or if the problem gets worse, time to replace the lifters.

webb06 · Jan 23, 2014

I wouldn't bother messing with it.

Dzchey21 · Jan 23, 2014

I think i would do an oil clean and some BG MOA in the oil on a fresh oil change and see if that fixes it

Boyce604 · Jan 23, 2014

I just changed oil 2000 miles ago. But can again. It only does it while cold out. Once it warmed up to mid 30 it still did it but very very very faint. But when it was in teens it was loud.

Supposed to be 50 this weekend and imma see if it still does it.

Why would it only do it when really cold. Guessing thick oil?

And what's BG MOA

Dzchey21 · Jan 23, 2014

zinc based oil additive that seams to work well on lifters

I had a 5.3 in a yukon that had one completly colaps and it fixed it

Boyce604 · Jan 23, 2014

I think last time I just used diesel oil from orielly. I think it was shell and a motorcraft filter. What brand is the BG MOA and what weight. Should I use. I'm used to gassers. Still learning on these motors.

Thanks for all the help guys.

Stroked777 · Jan 23, 2014

Boyce604 said:
I think last time I just used diesel oil from orielly. I think it was shell and a motorcraft filter. What brand is the BG MOA and what weight. Should I use. I'm used to gassers. Still learning on these motors.

Thanks for all the help guys.

BOA is a BG product that you add to the oil, its an additive
i think because of the high capacity if these motors you gotta add two but i cant remember at this point, make sure you leave some room in the pan to add it, i think its pint each