How to understand compression issue. Rings or Valves? Video attracted

[malibulr4]

I paid 12k for the car when it had 120k miles. It came with a nice full length roof rack, a Warn winch with PIAA lights. Now at 150k miles with almost all the routine maintenance done including transmission service. The only outstanding item was the timing chain.
Yes Stuart, it is smooth above idle. Any idea what a shop would charge to do the proper test mentioned above to assess if it’s just in the heads or a head gasket?The shop that sells the engines said the first thing they would do is some sort of wet test to determine if it’s the heads. They still said it would cost me about 6k round trip to replace the heads and to do the timing chain. I’m willing to drive at least an hour if anyone can recommend any great rover shops in the Los Angeles or Ventura area that could be trusted with determining if it’s just a heads.
Regarding the question about the codes I don’t recall the exact one but the mechanic the used the code reader worked at a dealership for 20 years and had a very expensive code reader that picked up the misfire. He also showed me another screen that was live showing active misfire counts with all the other cylinder showing zero misfires.

 

[djkaosone]

I would probably put money that your valves are heavily carbonized and your valves aren't completing the seal in the cylinder. I would try to walnut blast your valves, it's THE cheapest thing you can do to see if that's the issue. Once it's walnut blasted, I'd do another compression test to see if that fixed the issue.

Check out my post #39 where there was significant carbon buildup and after walnut blasting, also check post #53. How I walnut blasted it was on post #55. https://www.landroverworld.org/threads/diy-timing-chain.31050/page-4

On post #70, you can see my compression numbers. I don't want to mislead you with my thread, but great compression on all cylinders should be at 195-210 psi. When I run my compression test, I cut off ALL fuel and spark. This stops fuel from flooding the cylinder.

 

[timc930]

I'd do a leak down on #5, and see if it's blowing air into the block or out the intake or exhaust, that should confirm issues in the block or head.

BTW: How does compression in number 5 compare to the other?

As stated above (beemernut), Leak Down is a critical test to determine point of failure....Worthless to continue without proper diags..

 

[BeemerNut]

Somewhere in this thread I read of a"wet test", this a wet fart with lumps?

Hot dry engine leakdown compression check %, note down numbers then squirt in 5 cc's oil into the plug hole then rotate crack a couple revolutions and repeat leakdown compression check. Same numbers it's valves not rings. Now give it the hiss test listening at intake (I bet 5% issue) and exhaust pipe (95% issue) leaking valves.

That walnut shell blasting is BS in my book saw it done on BMW's when I had a 86 735 BMW, what a joke under warranty now burnt shells plugging up the Cats BMW had to replace LOL.

On the 95 Disco with new 4.6 it would form carbon buildup the back side of intake valves at 20K miles. Nasty buildup wanted to barf after inspection with an endoscope and laptop inspection a cheap tool addition to own.

I don't need no stinking expensive code reader to maintain an engine.


Removed plenum top and ram tube base allowing a straight shot at the intake valves.
Starting with cylinder number 1 by firing order placed at TDC compression. Paper towel plugged off other seven intake ports preventing carbon and dirt entering open intake valves.
Small parts tool pickup with claws and flexible shaft plus thick towel patches 3"to 4" squares soaked with Berrymann B-12 carb cleaner swabbed the back side of valve until spotlessly clean, smooth and carbon free.
Air blast out port number 1 then plug off. Rotate crank in firing order to other seven cylinders repeat cleaning process.
This way no carbon and crap particles entering the cylinder getting jammed between piston crown and top ring scratching cylinder bore plus imbedded into the soft aluminum pistons.

While apart valve seals with 215 Olds PTFE seals vs LR's POS seals, carbon buildup probelm solved. Rechecking intake valves at 85K miles again carbon buildup not an issue on these push rod engines known for carbon up being chugged around most their life.
Early on after new engine warranty expired an exhaust valve hung open randomly ending up with a burnt valve due to LR's crappy valve guides with engines running hotter with Cats in the USA. Grooved valve stems to saw away carbon from the guides the LR patch job. Replaced guides with magnanese-bronze, smooth stem valves replacing the carbon ring cutter stems
I run the LR engine up to 5,400 rpm's full throttle including in 5th gear of 5,125 rpm's hence carbon buildup not an issue inside the engines.

BTW, I had a connection with a Pick-Your-Nose friend at the pay and checkout and had the LR4 heads listed as 5.6 litre Toyota pickup heads hence the $250 for the pair list.

Timing chain while apart a good idea considering the bad track record of these 5.0 engines.
Build to LR specs for the machine shop to produce including quality of materials to the order of LR. Ford engine division produced the LR Vengine to LR's specs per contract not altering design and material quality.
***** people blaming Ford seeing a Ford Oval on the head castings.

*** do I know doing performing leakdown checks old before rebuild and after break in 1830 and 2800 Pratt & Whitney radial aircraft engines with A&P licenses awarded in 2/74 working under FAA and P&W factory guidelines?......End of novel......~~=o&o>.....

 

[djkaosone]

That walnut shell blasting is BS in my book saw it done on BMW's when I had a 86 735 BMW, what a joke under warranty now burnt shells plugging up the Cats BMW had to replace LOL.

I did it myself and I cleaned the crap out of each intake valve. Tedious, but I didn't want to get into a situation like yours. It made a difference to me, but I also did a ton of things all at once. So, there's that.

 

[malibulr4]

I love the lengthy posts! Beemernut I wish you lived close and I could learn a few things from you.! So I might call around and see if I can hire a mechanic to do a proper leak down test to determine the issue. Here’s a question for everybody. Let’s say it’s determined that it is one of the valves. Could a perfectly working low mileage head from a junkyard or crashed car be placed on my block? Can just one head be done?

 

[BeemerNut]

To really **** off the Pope I also have a Sun Investigator 1400 vs this 1115 Sun with the leakdown tester and capacitor checker.

For other hobby enjoyment a Hunter G111 four wheel alignment machine;

 

[BeemerNut]

I love the lengthy posts! Beemernut I wish you lived close and I could learn a few things from you.! So I might call around and see if I can hire a mechanic to do a proper leak down test to determine the issue. Here’s a question for everybody. Let’s say it’s determined that it is one of the valves. Could a perfectly working low mileage head from a junkyard or crashed car be placed on my block? Can just one head be done?

Unless your engine has been cooked (overheated) past life I bet 90% your issue is a leaking and now a burnt valve. Pull the head as you need to remove it anyway and disassemble it to see if a the seat can be dressed or replaced plus a new valve. Shooting in the dark not knowing condition here and a keeper i'd remove both heads and have them serviced whatever needs replacing. Check guide for clearances, valve stems and faces for wear as well the seats, go from there.

Heads for the 5.0 engines are very rare and hard to find plus very expensive used then your ending up with a pair of used heads of unknown condition.

One step at a time, have the bad head checked first if repairable. If yes check the other valves and head thinking freshening up seats and valves. New stem seals and be done. Added protection to replace the valve springs if your at high mielage. Dropped valve is ugly.
Money saved now towards replacing timing chains (sprockets if worn???).
Gasket set plus head bolts. Replace those damn plastic crossover pipes front and rear, they are rubbish and fail along with the timing chain guides another problem.
I mentioned making crossover pipes out of aluminum solving plastic failure issues. Thatv a different thread topic 6-8 months ago. Cut and Tig weld aluminum crossovers, machine ends entering the engine if, if I owned a 5.0 vs paying for plastic.
Had to ask, both fuel pumps still functioning, your not running on one?????

Not to **** off the 5.0 crowd just an opinion here. If I HAD TO OWN a LR3 or LR4 with engines options i'd take the push rod engine like the 4.6 then add a stroker crank making a 4.9 engine over these DFI 5.0 engines. Just my feelings after reading about the 5.0 problems and especially after wrenching on one.

I do not know if Mike Green at West Coast British in Livermore Ca. is into the cammer engines vs his LR training with the push rod engines. As an independant LR repair he hates stealerships with a passion......~~=o&o>......

 

[malibulr4]

Thank you all for the input. Found a shop that could do a proper compression test to determine if its the valves or rings. Still was quoted about $3500 for redoing a single head and about 4k for both heads. They quoted from the book that its 20 hours to pull a head. I dont like "the book" .
That leads be back to about $6k for heads and timing chain or $9k for engine at another place.
This may sound blasphemous, but I'm really wishing I had a Toyota Landcruiser right now! Timing belts are $900 to change!

 

[Stuart Barnes]

Thank you all for the input. Found a shop that could do a proper compression test to determine if its the valves or rings. Still was quoted about $3500 for redoing a single head and about 4k for both heads. They quoted from the book that its 20 hours to pull a head. I dont like "the book" .
That leads be back to about $6k for heads and timing chain or $9k for engine at another place.
This may sound blasphemous, but I'm really wishing I had a Toyota Landcruiser right now! Timing belts are $900 to change!

run it until it dies then do the Ls swap

https://www.landroverworld.org/threads/ls-swap-yeah-really.40150/