my only reason for not buying a 7.3 non turbo is because my friend who said he works on them is they have a problem with the last 2 cylinders. that after any amount of mileage they might scrap the walls thin and oil will work it way to the coolant and then at that point u need a new block? is this true? thanks

 

nope. the problem with the 7.3 was cavatation. if you do not use the proper additives to keep the coolant PH level in check, the block will deteriorate, and will eventually let coolant into the cylinder bore, most of the time the second from the rear on the passenger side, and when you try to start it it will hydro lock. then you will either have to replace the block, or have that cylinder sleeved.
if the Ph has been maintained and checked regularly, there is no reason for a 7.3 not to go to 350-400,000 miles. i have seen some over 500,000 miles, but most of the time the body rots off before that kind of mileage is attained.

 

tjc transport,
what kind of additive do you put in the coolant? im still a lil new at the diesel thing

 

Check out this page....... Cut and Past into explorer the redirector on FTE is screwed up goes to a dead end.......thanks guys!!!!!!!!!

http://www.arrowheadradiator.com/cav...ng_systems.htm

If you had oil in the coolant that would be oil cooler Orings leaking internally most likely... Coolant in the oil is usually Cavitation.........

 

thanks! that helps me out. i bought an f350 and they guy put new heads on it cause he said there was pressure in the radiator. well the truck used to be in a salt or fertilizer plant cause the hole thing is rusty and there isnt much left of the radiator. but my guess was cavitation cause i took the motor apart to rebuild it and the water jackets are pretty rusty. thanks for your help. i guess i need to have the block cheked for cracks.

 

Rusty in the cooling areas does not mean cavitation for sure. IH dealers usually have pressure testing equipment which involves putting a plate on the block and sealing off the cylinders. They then air up the cylinders to find any holes. If your engine was still together you could have done this test........

Cavitation Diagnosis
Source:
RPeter


--------------------------------------------------------------------------------
Updated November 7, 2001
As a 7.3L IDI & Powerstroke Ford technician I would like to clarify cavitation erosion diagnosis. I work on these engines all day every day and have developed my own test for this problem which has yet to fail me.

To accurately pinpoint the cylinder leaking the full steps are as follows:


Warm up the engine
Remove all glow plugs
Remove valve covers, rocker arms, and pushrods
Using an adapter that threads into the glow plug hole, attach compressed air (100-175psi)
Wait 3 mins for each cyl being tested.
A failed cylinder will make the Coolant level slowly rise and then overflow from top of radiator. It won't blow out of the radiator, but it will be obvious.
On Power Stroke Diesels a false failure may be indicated due to a leaky bottom injector o-ring. So, before you run off in a panic, consider that the o-ring may be defective, effect repair of the o-ring in that cylinder, then re-test.
NOTES:

Valve train should be removed to allow the piston, in the cylinder to be tested, to drop to BDC when shop air pressure is applied. This insures the valves will be closed and the entire cylinder surface can be tested under pressure.
You can purchase an air pressure adapter at most tool shops (they normally are sold to adapt a compression tester to the glow plug hole)
The cylinders that are most prone to cavitation are listed in order. #8, #7, and #4. Be sure to test all cylinders as I have seen some of the other cylinders occasionally deviate from this norm.
Most coolant leaks into the cylinder will show as the glow plug tip will be wet on the bad cylinder.
I have had very good success sleeving these engines in my business, but the key is finding a machine shop that has done this specific repair before. You don't want yours to be the machine shop's first kick at the cat!!.

 

no i dont think i could have...the kid i bought the truck from put new heads on the motor, when he was putting it back together, he didnt get the dipstick tube back in the hole. so he drove it 12 yes 12 miles and the motor locked up. well i bought it took it home, pulled it from the truck and pulled the oil pan off. it def needs new bearings,, the crank looks ok (towards the front there is some small blue discoloration but not bad) so i have to have the crank checked and turned. the cam needs new bearings, the cylinders have a noticible grove at the top where the piston goes back down (ridge reamer will take care of it) but im sure the piston rings got way to hot so it needs those. and the block needs to be checked. i know that it can still be checked w/out it being all together (but i left the crank, cam, rods, and pistons in it so that it can be checked. also the heads can be re installed w/ a new set of gaskets. but im at college so the only time i get to work on it is on the weekends. so if i make the 3hr trio home this weekend i will try to get the block checked. do you know what a good price to have a block boiled out costs? ive only had it done once on a 4cyl and i dont remember the cost. thanks again!

 

there are allot of different types of cooling system additives. standadyn, and motorcraft are 2 i know of, and i use napa-kool. every 6 months i check it with a ph strip, and add some if needed till it reads in the safe range.

 

ok thanks. do you get the ph strip at the local parts store too i assume? (NAPA)

 

yup, napa has them, i think they are $45 for 100.