Sludgy 1990 F150 5.0

[cbrf3]

Son bought the truck with we are told 121000 on it and overall it looks correct. It starts/runs well and seems to have decent power. He tore into the intake to clean and decided to take the valve covers off. So the heads are not so pretty as we believe the truck sat for about 6 years. He has cleaned a decent amount of the sludge out by hand and the next step is to run some M1 EP HM 5-30 for about 3k miles.

My question is how long to run the filter. We have a Fram Ultra and a Tough Guard. Think either one should be run the full 3k?
I am more interested in a slow clean and am not concerned with the cost of the oil nor the filter just do not want to push the filter to bypass.

 

[JC1]

I would change the oil filter after 500 miles and cut it open and see what's inside. Depending on what you see would determine how often I would change the filters. Just get some cheap supertech filters at Walmart or equivalent from rockauto and do that until you feel comfortable that the sludge is going away.

 

[ctechbob]

Personally, I wouldn't rely on oil to clean that up. I would pull the drain plug and use a solvent and brush and get as much as possible out before you go to wasting a lot of oil. Once you finish, button it up and run a short change of oil and go from there. You'll want something that won't hurt the valve seals, so no brake cleaner, but perhaps some kerosene or the like.

 

[tiger862]

I wouldn't worry about it. Close it up with new gaskets and run synthetic oil of your choice for 5k. I have seen worse and they ran a long life on conventional oil with 3k oil changes. I had 2 used vehicles that I bought as is so I had no idea until I fixed valve cover leaks. Both got over 50k with one blowing lower hose on interstate wiping out motor and other got traded in for newer vehicle. Neither died from sludge. My dad tried to clean a sludge motor in Mom's Oldsmobile and it smoked afterwards using lots of oil. He wished he had not cleaned it cause it didn't use oil before.

 

[2EHA]

run supertech or rotella why waste expensive oil in a 3k interval.

 

[Schwifty]

Put some PP to the test and swap the oil filters every 500. What’s the goal for this truck?

 

[JeffKeryk]

Shell Rotella T.

 

[Chris142]

I would remove the drain plug then pour a few gallons of diesel fuel all over the rockers and heads to wash the loose stuff out.

Then run cheap oil and good filters. Changing them often. Like every 500 miles for 2-3 times. Then run it till it blows.

 

[blufeb95]

Flush it real good like others have suggested then go to a Cummins Service Center and get some Valvoline Premium Blue Restor and run that for an OCI.

 

[Oro_O]

Personally, I wouldn't rely on oil to clean that up. I would pull the drain plug and use a solvent and brush and get as much as possible out before you go to wasting a lot of oil. Once you finish, button it up and run a short change of oil and go from there. You'll want something that won't hurt the valve seals, so no brake cleaner, but perhaps some kerosene or the like.

Exactly. Brush on warm kerosene or diesel and let it drain through.

Then fill the engine with cheap 10w40 to -1.5 qts. Add that much kerosene or diesel and let it idle 20 minutes. Cool down and repeat. THEN drain it all out and start with good oil and filter.

 

[demarpaint]

Good oil isn't going to clean that up anytime soon, even doing very short OCIs. A while back Trav had posted a good method for cleaning that type of mess up. I'd PM him, he might be able to provide a link to it.

 

[SWS]

Welcome to BITOG!
Your comment, “It starts/runs well and seems to have decent power” is significant.
Also your stated goal: slow clean.
Your son has taken good first-steps, so I suggest caution & ‘do no further harm’.
Your plan & oil choice are good to get you on the road soonest with lowest risk. Check that the oil drain-backs to the pan are open, then close it up and drive it.
As already suggested, changing the filter at 500 miles is a good idea and the debris you find inside will guide your next-steps.

If your plan does not provide the results you want, then you can always take the more aggressive cleaning steps later, at low cost.

Personally, I would move on to checking / flushing the brakes!

 

[PontiacHO]

close It up and drive. It won’t last any longer attempting to remove sludge from the top that will likely fall in the the lifter galley anyway. It’s pretty much that way through out. thats a “puddin motor”. The only real solution is disassembly and the acid bath.

 

[dlundblad]

I’d keep the truck on a strong diet of Mobil 1 0w40 personally. 3-5k intervals depending on his driving.

As for the filter, I’d start at 500, cut it open and take a look. Might need another 500 might be fine for the whole OCI. Run Fram Extra Guards, Supertech or the cheaper WIX from NAPA.

 

[Amkeer]

Just put oil in it and use it. You are not going to clean that up. Trying to will cause more problems that you don't want to introduce.

 

[OVERKILL]

If the heads look that bad the valley is going to be WAY worse.

I like Chris142's suggestion with diesel or kero and a toothbrush to get things cleaned off. A FRAM Ultra with M1 0w-40 would be my oil of choice once you've got it suitably cleaned. Cut open the filters to confirm the interval isn't too long, start at maybe 500-1000 miles and go out from there depending on the accumulation level.

M1 0w-40 is one of the very few PCMO's on the market where the manufacturer has actually provided before/after pictures of cleaning up existing sludge/varnish. Most advertising revolves around keeping things "up to" X amount cleaner than other oils.

 

[SatinSilver]

This.

 

[cbrf3]

So I think the Supertech filters for a bit and opening them sounds like a good idea to see what is happening. The goal is to make this a daily driver. The brake fluid has been replaced, we are working on trans/fluid and the coolant is next after all of the hoses are replaced. The oil drain backs are clear as we put wooden dowels down them to prevent debris from falling in and the sludge has been scooped out.

The M1 HM was bought for about $1.85 a quart so it is not too painful to use.
Interesting that the suggestions are from it is on its last legs to do not worry about it.

 

[BLND1]

Rebuild time! A set of GT40 heads will do the trick.

 

[Pablo]

Do you know what the maintenance history is at all?

Hardly changed oil of course. Nasty.

My recommendations are similar to the above about cleaning. Easy does it with 500-1000 mile intervals 3-4 times, then after that like the 4-5th time use an IDLE only type flush then drain for hours/over night and again withe the short intervals. Repeat. I bet slowly but surely it cleans up and will run OK if it runs fine now!