Thread: URGENT HELP NEEDED FOR LR90 on Route

This is common problem with the 2.5 n/a and the 2.5 Turbo

The 2.5 after all was a bored out 2.25 and the 2.5 Turbo was just a 2.5 with a turbo wacked on. BTW The 2.5 Turbo had a life of about 70,000 miles before it blow up.

I don't believe Australia had the pleasure of these engines

I had all three of the engines in a S3 (2.25 ) and a couple of 90's

My 90 2.5 did just the same as this one and was a common thing with the 2.5's to transfer oil into the air filter when the engine was worked hard. I tried to fix this but gave up in the end as it did not seem to effect the engine or oil.
But if the oil is excessive then that is not the norm, the norm was damp with oil and not soaked with oil

You could try and check the Cyclone breather diaphram as if this is blocked the oil with go up from the rocker cover breather into the air filter

But If you have a worry , the cylinder you want to look at is number 4 as it is furthest away from the rad and cool air so it gets the hottest of them all.
I did have a 2.5 that I had to rebuild because the rings we gone. But showed no normal signs just crank case pressure that blow out the rear main. Took me a while to work out that was what it was. In fact two rear main oil seals and 3 head gaskets later

But they are an easy engine to work on . I got the head gasket change down to an hour and half in the end

But to be honest if you have all the pistons and rings out then I would put new ones in out of matter of course. Because even though I have said it could be a few things one of the things it could be is crank case pressure which would caused by the rings so changing them would fix it and while you are in there you would mad not to change them

Well the weekend has passed and we are still in Goondiwindi. Making the best of a bad situation there was a B&S Ball on so to keep our spirits up we headed along to that

Before the bundy....

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After

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Only to have our hopes dashed of getting away tomorrow because the courier company an only confirm it will arrive at some point before close of business tomorrow ....we had hoped today...the parts are only in Toowomba. Might have been quicker by Australia post....

Well, we are still here. Very frustrated and very confused. In fact...stumped. Beginning to feel like Goondiwindi's news residents.

Yesterday

Parts arrived yesterday, head gasket and rings. Great. Pistons in, new head gasket on, following the instructions in the manual that say the "Diesel" lettering should face uppermost. Bolt it all up, fill her up with coolant only to find it all ****ing out along the passenger side of the hear. Turns out the manual is wrong and it goes the other way round otherwise it does not block off the water gallery in the head....! Checked the original gasket and, it goes on "Diesel" facing down. Lesson 1 learned for the day.

Today

Fired the landy up, still getting blow back. Blanked off the vac pump, still getting blow back. So we run a decompression test on all cylinders. Seems that it will fire and run on 3 pistons when #2 is decompressed, but when any of the others is decompressed it will not fire/run. Suspect #2 has a problem.

Top facing of picture = front of engine. Note, no carbon build up in #2 and mark where valve has hit piston - not sure if from when we put the head on or not checking rockers/tappets

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Pull head (Again). Note that #2 piston is oily and not covered in carbon and a little diesel. Also note the inlet valve has bashed the piston.

Head. Top of picture = front of engine. Note #2 piston is oily/diesely....

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Lesson 2, always check tappet clearances when putting it all back together.

Lesson 3. Even though the rings may look fine and measure fine, they can still be stuffed. So we decided that we would hav.e to replace the rings aswell

Plan for the day...pull head, check valves, install new rings, put back together

To be continued.....

Today continued

So decompression test and head of this morning. Purchased a valve compressor, lapping tools and paste. Removed inlet valve from #2 piston and checked it over, not bent, no cracking of valve guide...replaced stem seal. adn re-lapped it and then went about checking every valve and re-lapping them too.

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Borrowed a ring compressor (Again) and a bottle brush hone. Dismantled the pistons, one by one and replaced the rings and gave the bores a light hone

Old rings...

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New rings....

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It was noted that there as visible difference in wear in the new rings, with #1 and #2 pistons rings showing no sign off any taper or chamfer to any edges, with #3 and #4 pistons showing a very very small amount. Perhaps that is it?! What is causing the problems?

Yet again, the instructions were not very clear as to which compression ring goes where. The data sheet says #1 compression rings is tapered and chrome plated, and #2 square cut. Instructions state the opposite. Good work Land Rover Workshop Manual! A few phone calls later (MR Automotive) and the top one is the chrome tapered variety and #2 the square cut one....

Work went on late into the night, with the head finally going back on at 7.30pm

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Tomorrow, head gasket on, torque up, rockers/tappet adjustment...fire it up and hope the the best. I am sure we are due some good luck soon....

Can't help with the actual problem - but if the engine actually runs I would be tempted to buy up on oil (and degreaser) and irrespective of whether you have blow by or not I would be on your way.

It might make a mess but it is not likely to stop going in the short term.

Good luck with it.

Garry

Sounds like you have a copper head gasket?

VHT copper spray is worth the $$$. Apply a liberal coating to both sides.

Hi Fellows

Before you put the exhaust back on, run / idle the motor till it is warm, and check then for blow by, by giving it a noisy rev or two.
Then let it cool for a while, put the exhaust system back on and do the same again.

Look out for the possibility of the muffler being choked up.

Cheers Arthur

Originally Posted by Reads90

This is common problem with the 2.5 n/a and the 2.5 Turbo

The 2.5 after all was a bored out 2.25 and the 2.5 Turbo was just a 2.5 with a turbo wacked on. BTW The 2.5 Turbo had a life of about 70,000 miles before it blow up.

I don't believe Australia had the pleasure of these engines

I had all three of the engines in a S3 (2.25 ) and a couple of 90's

My 90 2.5 did just the same as this one and was a common thing with the 2.5's to transfer oil into the air filter when the engine was worked hard. I tried to fix this but gave up in the end as it did not seem to effect the engine or oil.
But if the oil is excessive then that is not the norm, the norm was damp with oil and not soaked with oil

You could try and check the Cyclone breather diaphram as if this is blocked the oil with go up from the rocker cover breather into the air filter

But If you have a worry , the cylinder you want to look at is number 4 as it is furthest away from the rad and cool air so it gets the hottest of them all.
I did have a 2.5 that I had to rebuild because the rings we gone. But showed no normal signs just crank case pressure that blow out the rear main. Took me a while to work out that was what it was. In fact two rear main oil seals and 3 head gaskets later

But they are an easy engine to work on . I got the head gasket change down to an hour and half in the end

But to be honest if you have all the pistons and rings out then I would put new ones in out of matter of course. Because even though I have said it could be a few things one of the things it could be is crank case pressure which would caused by the rings so changing them would fix it and while you are in there you would mad not to change them

Yes 100% agree the Turbo Diesel 2.5 is a abortion of an engine..... Here's one that failed 3 weeks ago at a friends garage. So they are still failing 20+ years after they were new.

75,000 miles from new serviced by same garage from New.... 3 Weeks ago coming up a hill no load in the vehicle just an empty tray, Changing from 3rd into Top... And BANG!

Photos speak for themselves.... We think it could of been a Big end cap bolt failure

And the end of it all in late 1980s they up rated the block and crank which gave us the 200Tdi. But sadly Land Rover Engine development between 1958-1998 was really only updates on old designs basically trying to get away with the minimum Eg. as Reads90 says Boring a 2.25 to Make a 2.5 Turbo but change nothing else!