Advice please

[gnxtc2]

Nowadays, most mechanics don't want to diagnosis issues. They jump to conclusions and run with it.

Unless you did something stupid (overheat, bad tunes, etc, etc) t is very hard to blow head gaskets on a 7.3. The cylinders have 6 bolts making the seal.

You'll kill a stock turbo at 30lbs before blowing head gaskets.

Billy T.
[email protected]

 

[gnxtc2]

Thanks for the responses. The coolant seemed perfectly fine but the oil not so much. I went ahead and gave the ok for the compression test.
The heads were originally removed due to coolant getting everywhere and steaming out of the tail pipe- new cups injectors and so on. Wish
I had the knowledge of doing a compression test then. Anyhow that was two years ago. I did recently replace the oil cooler and add an oil bypass to the oil system.

My compression test from the mechanics shop:
1-360. 2- 400
3-360. 4- 355
5-380. 6- 380
7-380. 8- 400

The shop wants $1800 to remove the heads then inspect. Cost includes new gaskets and reinstall. Torn on what to do.

A new engine will have around 410-420. Was the test done cold? The numbers are all over the place.

When the heads were originally done, was the issue still present?

Billy T.
[email protected]

 

[Rico]

A new engine will have around 410-420. Was the test done cold? The numbers are all over the place.

When the heads were originally done, was the issue still present?

Billy T.
[email protected]

The issue went away when I re installed the heads years ago.
The compression test was done cold.
This issue just arrived, first oil change since I recently completed some work on the vehicle. I took the truck in to a mechanics shop since I noticed a serious miss and ran a CCTest. Showed cylinder number 6. Buzz test passed. I pulled off the valve covers and saw a milky looking oil. I went ahead and disconnected each injector manually and they all seemed to make the same difference except cylinder #4. I changed my oil, took 1/2 a day it was so slow draining. I thought the oil might have just broke down, I did hit some stretches driving and got the boost damn high. After torque down of all the injector bolts I ran the same manual unplugging of each injector plug. They were all even. I did flat edge each rail of injectors and they were not all level with each other but not sure if that matters.

 

[Rico]

Mechanic quote is ten grand for rebuilt long block installed with no warrenty due to all the changes I’ve made to the motor. Think I’ll take her home and rebuild the motor by doing as much work as I can. Looking for a second vehicle if anyone might know of an OBS for sale

 

[79jasper]

I have a 94. Single cab though. Lol

Sent from my SM-G892A using Tapatalk

 

[Rico]

Well I bought a 1997 F350 with a 460 yesterday. Now do I part out my diesel, save the parts and sell a rolling chassis or sell the truck in all. Synch RO’s are shot, motor compression is funky and there’s coolant in the oil. Eventually I want to buy a 97 7.3 when I can save up the money. :/

 

[JCart]

If it were me I’d double check the stock oil cooler to ensure the orings are in place and make sure there are no defects in the cooler itself. I’m thinking injectors should all be same depth in head too.

j

 

[Rico]

I agree. I think it’s the o rings in the mount closest to the radiator. But with the miss fire and the compression numbers I’m leaning toward selling and saving up for a crew cab

 

[Rico]

Can I diy check the oil cooler for any defects? I really want a diesel crew cab but it’s hard thinking about letting my truck go. I fired up the truck and it sounds down right dangerous. Love it. Except for the slight miss. The miss is weird because the truck passes a buzz test and a cylinder contribution test.....

 

[JCart]

Review the front engine casting where the front of the cooler bolts to. If you overtighten the front bolts it can cause the engine cover casting to crack (don’t ask how I know....), causing (mine leaked external antifreeze). I’d check for hairline cracks in this area. I’d also look closely at the front cooler to block gasket. In respect to the cooler itself, correct me if I’m mistaken guys, but the oil pressure in theory is higher pressure then the antifreeze so oil should contaminate antifreeze system first no? Although after shut down perhaps antifreeze is contaminating oil system as it may stay pressured longer?

Also just throwing it out there, if the fan bearing is bad it can cause the impeller to chew a hole in the front aluminum engine cover next the block, wondering if antifreeze can migrate into top of oil pan if this happens?

j

 

[Rico]

The fan seems to have no wobble. There’s no exterior coolant leaks and no sign what so ever that there’s oil in the coolant. When I installed the new oil cooler with new rear oil filter mount I had left in the front mount and just pryed the rear mount with cooler in. Possibly the o rings didn’t seat properly? Either way I have one cylinder that nearly 50lns lower in compression than the others. With the feedback from a few mechanics they just suggest rebuilding. Not sure what to do. I might just sell it as a rollin chassis

 

[505yam]

take the oil cooler back off and inspect the oring that separates the oil from the coolant. I have seen several trucks where someone had recently replaced the oil cooler orings and nicked/ cut the oring when installing the end housing back onto the cooler and it causes oil and antifreeze to mix.

 

[Rico]

Will do. Any recommendations on a diy compression test

 

[old man dave]

Will do. Any recommendations on a diy compression test

Harbor Freight sells a $30 dollar diesel compression tester set. Some people say it has an adaptor that fits the 7.3. I'm not sure.

My buddy made me an adaptor out of an old glow plug, steel tubing and one of the fittings out of the kit. Just brazed it together after drilling out the glow plug. Tubing section is about 6" long to clear the rocker arms.

https://www.harborfreight.com/diesel-engine-compression-tester-20-pc-62594.html

 

[old man dave]

take the oil cooler back off and inspect the oring that separates the oil from the coolant. I have seen several trucks where someone had recently replaced the oil cooler orings and nicked/ cut the oring when installing the end housing back onto the cooler and it causes oil and antifreeze to mix.

A heavy duty ratchet strap works good to reassemble the cooler if you don't have a press. I had my engine on an engine stand so I mounted the cooler one side only and squeezed it until the other end's bolt holes lined up.

 

[ju015dd]

Did u ever pull the injectors and pressurize the coolant system?

 

[Rico]

I have nt done a leak Down test. But this happened right after I swapped the oil cooler

 

[Rico]

Well finished a compression test today. All cylinders seem near 380-400 except cylinder 5 that is at 340-350. Added oil to the cylinder, turned motor over, installed compression gauge and I got a 400 lb reading. What to do? riest:riest: