My truck is a POS

[9073]

Here is the colorful history i have had with my lovely pile of junk.

I bought the truck last december and loved it until about a month or two ago.
I always noticed that the idle was set to high.

Last month the truck started having serious problems with the oil pressure.

I checked the spec on alldatapro.com and it says oil pressure should be between 40-70 psi at 2200 RPMS on a warm engine.
I installed a mechanical guage with a cappilary tube and that is how i got that reading.

Beggining last month i began my project, I pulled the motor and installed new rods,mains and an oil pump. I then reinstalled the motor and it held really good oil pressure 50 psi hot at 2200 RPMS (well within spec range). Then i went to move the truck and the throw-out bearing was torn to pieces (ok my fault) But the point is it had very good oil pressure.

I then took the motor apart from the tranny to do the TOB and reconnected everything and then had a feul system problem (see my post titles 7.3 no start)

After fixing that last night the motor started and the first thing i noticed was low oil pressure.

Sure enough i let it run up to operating temperature and the idiot light comes on and my mechanical guage reads zero (well its actually like 2 or 3)

My theory is that the previous owner knew about this problem thats why he turned the idle up to 725 rpms and he also mentioned that i should run "straight 30 weight oil because its an old truck" I was ripped off by another member of this site who will remain nameless.

I need this truck for work (landscaping) and the bottom line is I would be willing to sell it if anyone is interested.
Here are the few good things about it
2 Brand spankin new batteries (1 day old)
Newer stanadyne injector pump
newer radiator
decent tires
new clutch mas cylinder and slave cylinder
new throw-out bearing
new front shocks
new rear brakes,hardware and wheel cyinders and line.
newer stainless steel 3 in exhaust from y splitting back
new oil pump
new rod and main bearing
fiberglass truck cap
bedliner
kn air filter

and i have a set of brand new tires (2000 miles roughly) and rims (ford factory rims 8 lug fits these are mounted and balanced.
the truck itself is a 4x4 f-250 3.55 gear ratio zf five speed

Sorry for the long post but i need to take anger out somewhere.
Thanks
Matt

 

[EvergreenRanch]

Matt i sympathize. If i wasnt mechanically inclined, i would have never bought this truck in the first place. you certainly seem to know basic mechanics. oilburners is an excellent reference, with people willing to help. if you have simply given up, im sorry....if not, lets try and figure out whats going on with the engine....i know i learn a tremendous amount just from what other people have gone through with their trucks.

ok here's a few regurgitated things to think about:
a. The high viscosity of the engine oil did not allow oil pressure to build quickly, and may also have caused the system to go into bypass, thus the low oil pressure.

b. Possible engine damage may include; scored engine oil pump - damaged lead/tin overlay of crankshaft bearings (mains and rods) - damage to camshaft bearings - damage to lifters - damaged small end bearings of connecting rods - damage to bearings of engine timing/idler/accessory drive gear train

c. Solution would be to change engine oil and filter. Install a multi-viscosity oil such as 10W-30 or 15W-30, or install a low wattage engine oil pan heater (stick on or magnetic)

d. Lube oil tests that show the viscosity at 40°C and 100°C would indicate that oil has degraded from new. Soot loading would be high. Oxidation and sulphur would also read high.

e. In this unit (diesel engine), soot loading would be the primary factor for the increase in viscosity. Soot loading also increase the oxidation rate of the oil, which in turn increase the viscosity. Sulphur in the oil (from fuel) could also be high, either from extended oil change intervals, or, from the engine running too cold (cooling system problem or short operating cycles). Condensation (and the rise in acid formation) would also be a factor in a cold running engine. All of these, combined, would lead to a severely degraded oil, with high viscosity, in a short period of time.

Also, you mentioned that you replaced bearings and so on.......did you do any sort of priming to ensure a lubricated startup? whats the temp like in Columbus at the moment? i live in california so im not too familiar with the issue, but i know at lower temp some oils will gel. id do a system flush, change the oil and the oil filter, and prime the engine......and dont get frustrated....doesnt help anything.

 

[bikepilot]

I don't think you want a 5w-30 or thinner in an IDI for normal tempatures. Even straight 30 flows fairly well in normal (say above freezing temps). My dad put 200k miles on his 6.2L IDI with straight 30 in it. If you replaced the oil pump and main bearings that should have fixed the low oil pressure problem - I can't see what could have been worn out by the po that you haven't fixed. Also, its odd that the pressure was fine before you did the TO bearing and fuel stuff. Perhaps the oil got diluted with diesel during your fuel problems:O

Good luck

 

[Mr_Roboto]

Before you get all worked up...

The oil pressure relief valve for our engines is located in the cooler header, not in the oil pump like most engines. If the relief valve got a pice of crud stuck in it, it will dump all the oil back to the oil pan and you will have no pressure.

Also, did you check the oil pickup screen when you changed the pump? If it is clogged with sludge you will also get no oil pressure (been there).

There are two recommended oils for our engines, 30W and 15W40. In our area, 30W is fine for summer use, I personally use 15W40 year round. There really is nothing good or bad about using 30W in warm weather, and using it won't cover up oil pressure problems.

BTW, if you need a truck to get by for a while, I have a 93 F150 X-cab with a 300 gasser for $500. It's a piece of crap, but it runs. I'm over in N Ridgeville.

 

[stiesel]

i feel your pain. when my truck is giving me problems i am not fit company for man nor beast.

i run 15w40 all year.



.

 

[Agnem]

Looks to me like the oil presure problem isn't related to the rebuild. The return of good presure may have been a coincidence due to handling. I'm thinking cooler header also, or an obstruction.

 

[icanfixall]

The spring in the oil pressure regulator wears almost in half because its sliding on a hardened cylinder. The parts are not rebuildable but for about $160.00 you can buy the complete rear oil cooler header that has this regulator in it. Its not too hard to do but takes some planning. First off do you want to lift the motor. Or do the work from the top side and remove the drivers side exhaust manifold or do it from the bottom and just leave the front header in place. What ever you do plan it out and replace the oil cooler o-rings while your in there. Plenty of help whichever direction you plan on. The PSD motors have a rebuildable regulator that has a snap ring retaining it together in the rear header. Ours are staked into the aluminum housing and removing them from said housing leaves very little metal to hold them in place for reassembly but it could be done if parts available. Don't give up on this. It hurts now but will be fine in short order.

 

[9073]

evergreen ranch- The weather over here in Cleveland is warm this time of year. Today i believe was in the 70-80 degree range.
The oil i run is rotella 15w-40. I use this year round.

The oil pickup screen was cleaned.

My buddy's dad is a diesel mechanic and also believes that it is the oil pressure relief or the camshaft bearings.

I am thinking that i will pick up a reliable vehicle while I completely rebuild the engine in the truck and when its done it will be like brand new.

Mr Roboto-Thank you for your offer but my dad has several vehicles in mind.

Thank you everyone
Matt

 

[EvergreenRanch]

glad you've not given up on it....believe me there have been several times that ive gotten so frustrated with this truck...well lets not even think about it but yeah....

 

[Agnem]

I don't think it's been mentioned how many miles are on this engine? They don't have a history of being ******* bearings unless it's been abused, so your rebuild may be premature, although certainly not unwelcomed.

 

[9073]

Agnem- The actual miles on the truck are about 210,000.
The previous owner said that the engine was rebuilt about 100,000 miles ago.

I do believe that someone was in the engine before because instead of putting a gasket in they used the permatex gasket maker


Matt

 

[Agnem]

If your talking about the oil pan, I believe that may be correct. To the best of my knowledge, there is no gasket for the pan. Just the blue goop.

 

[dbarilow]

has anyone ever tried to make a gasket for the oil pan? we used to get rolls of rubberized cork to make gaskets in the field along with gasket paper

http://www.vellumoid.thomasregister.com/

 

[Diesel JD]

Advance Auto Parts shows a gasket for them, but I don't know how they came from the factory.

 

[tonkadoctor]

My theory is that the previous owner knew about this problem thats why he turned the idle up to 725 rpms and he also mentioned that i should run "straight 30 weight oil because its an old truck" I was ripped off by another member of this site who will remain nameless.

Beggining last month i began my project, I pulled the motor and installed new rods,mains and an oil pump. I then reinstalled the motor and it held really good oil pressure 50 psi hot at 2200 RPMS (well within spec range). Then i went to move the truck and the throw-out bearing was torn to pieces (ok my fault) But the point is it had very good oil pressure.

Sure enough i let it run up to operating temperature and the idiot light comes on and my mechanical guage reads zero (well its actually like 2 or 3)

I do believe that someone was in the engine before because instead of putting a gasket in they used the permatex gasket maker

Let's see if I can cover a few issues here.

Straight 30 weight oil isn't thick enough when warm to cover up problems with bad bearings at temperature, Your 15w-40 has a higher viscosity when hot than straight 30. You would have to use straight 50 weight or higher(most likely 90 weight gear oil) to do that which is why that "motor medic" stuff you buy at the parts stores walmart etc is as thick as cold honey.

When an engine loses pressure at operating temperature it is usually a sign of bad main bearings.

If I remember correctly this is your first rebuild so here are a few questions for you.

If the engine has been rebuilt before, the crankshaft may have been turned down .010 - .030, did you check that before installing new bearings, if not and you installed a set of standard bearings you may have huge gaps that are allowing the oil to just slide by and not build pressure.

When installing the new bearings did you use assembly lube, if not they could have already destroyed themselves on the first start up.

Did you plastigage the new bearings when installing the crank. If the clearances were too tight the bearings would self destruct and if the clearances were too loose the oil won't build pressure.

All manufacturers use RTV instead of gaskets on oil pans valve covers etc, anywhere they think they can get away with it....Saves them time and money...This practice started many years ago.