Technical Mk I 2.5TD valve and seal replacement

Homer123s · Sep 28, 2015

Thought I'd start a new post for this one, pretty sure now that I have a problem will leaking valves as oil appears to be present in exhaust manifold above the turbo.

What I'm looking for is some idea of what the likely cost of doing the work will be. Any thoughts appreciated.

corcai · Sep 29, 2015

You can do them without the head off with compressed air to push the valve up. Or you could put in 15w40 high mileage oil and forget about it. With the mileage campers do its not likely to get much worse.

Homer123s · Sep 30, 2015

corcai said:
You can do them without the head off with compressed air to push the valve up. Or you could put in 15w40 high mileage oil and forget about it. With the mileage campers do its not likely to get much worse.

Not sure you can, its an OHC engine, not even sure about how to get a seal for compressed air. The injectors do not screw in, they are held in with a yoke. I'd guess you would get some air leakage but I guess I'd never know unless I tried.

corcai · Sep 30, 2015

Compression testing kits come with dummy injectors where a glow plug isn't present any decent garage will have a set.

You only need 80psi so a bit of leakage isn't much of a bother if you have a half decent compressor and a line regulator.

Off the top of my head I would say you could clamp something like a 3/8" NPT for 20mm injector or 1/2" NPT for 24mm injector fitting with a piece of tough rubber hose over it for a seal into the top of the injector hole. You might have to grind the corners off the fitting.

Homer123s · Sep 30, 2015

I have a compression test kit and have modded the dummy injector supplied to mirror the actual injector, has also made the compression test a lot more accurate. I guess I could mod one of the connectors and connect up to compressor.

Only problem is, as far as I'm aware I still can't get to the valves without stripping part of the engine, cam shaft in the way and there is no direct access to the valves or so I'm told.

corcai · Sep 30, 2015

Homer123s said:
I have a compression test kit and have modded the dummy injector supplied to mirror the actual injector, has also made the compression test a lot more accurate. I guess I could mod one of the connectors and connect up to compressor.

Only problem is, as far as I'm aware I still can't get to the valves without stripping part of the engine, cam shaft in the way and there is no direct access to the valves or so I'm told.

With the compression you've measure I wouldn't be thinking about replacing the valves just the seals if the smoke at startup is terrible.

Homer123s · Oct 1, 2015

Have you ever taken one of these engines apart. I'm struggling, I can remove all the pipes going to the turbo from the air intake and the intake manifold. What I'm struggling with is removal of the intake manifold and exhaust manifold, they are not very accessible from what I can see and they need to come off to get the head off so that I can get to the valves. A garage might be the easiest option

jontee61 · Oct 2, 2015

Checked with my friend who happens to be brilliant mechanic and maintains my van which is same engine I think 1996 fiat 2-5 turbo diesel injection and he assures me that the seals can be replaced Without removing head and if you have a Collette removal tool job can be done very quickly.jt

Homer123s · Oct 2, 2015

jontee61 said:
Checked with my friend who happens to be brilliant mechanic and maintains my van which is same engine I think 1996 fiat 2-5 turbo diesel injection and he assures me that the seals can be replaced Without removing head and if you have a Collette removal tool job can be done very quickly.jt

Engine in mine is an 8144.21 Sofim single overhead cam, surely the cam will be in the way so that will have to come off which means locking up the crankshaft and the fuel pump before removing the timing belt. Putting that on first time around wasn't much fun, not sure I can go through all of that again.

interested to know if I have understood this correctly, I'm not a mechanic so some things I don't fully understand, I'm having fun learning though.

corcai · Oct 2, 2015

Cam will have to call me out to do the seals . I've only worked on the the mkII 2.5 I think I had to use 1/4 inch deep sockets for a couple of the manifold nuts and a 1/4 flex which is still twisted to this day. I would not be taking the head off an engine with good compression.You are going for the biggest job before ruling out the little ones.

Homer123s · Oct 3, 2015

corcai said:
Cam will have to call me out to do the seals . I've only worked on the the mkII 2.5 I think I had to use 1/4 inch deep sockets for a couple of the manifold nuts and a 1/4 flex which is still twisted to this day. I would not be taking the head off an engine with good compression.You are going for the biggest job before ruling out the little ones.

Taking the head off would be the last resort but I am struggling to determine what else it could be.

Compression is good and injectors are fine. I'm not a mechanic so struggling a little here. To me that only leaves the turbo or the valve train.

I do have one question regarding the timing. could this have been out before we put the new belt on.

Also the cam seal on the timing end was leaking, could this have been pushed out by a build up of pressure, there is pressure when the oil filler cap is removed

digger58 · Oct 3, 2015

If you are getting pressure build up on the engine I would suspect worn rings! Is the breather clean? What mileage on it?

corcai · Oct 3, 2015

Homer123s said:
Also the cam seal on the timing end was leaking, could this have been pushed out by a build up of pressure, there is pressure when the oil filler cap is removed

At tick over you should only have 10-15 liters per minute blowby if you have loads then its rebuild time.

Homer123s · Oct 4, 2015

Thanks guys,

Is there an easy way of measuring blowby?

Mileage on van is 107,000 and there is no breather on the rocker cover, there is a box on the crankcase which has a gauze filter built in to it, I've had that off and cleaned it out, it looks okay.

Are there likely to be other breathers?

corcai · Oct 4, 2015

Homer123s said:
Thanks guys,

Is there an easy way of measuring blowby?

Mileage on van is 107,000 and there is no breather on the rocker cover, there is a box on the crankcase which has a gauze filter built in to it, I've had that off and cleaned it out, it looks okay.

Are there likely to be other breathers?

Thats the breather, make sure the hose to the intake isn't kinked or blocked.

Adult lung capacity is about 6 liters so if you blow out slowly it will give you an idea of how little blowby there should be at tickover. You don;t need to measure it if its as bad as you describe.

Homer123s · Oct 4, 2015

I'll check the hose tomorrow, might have a gauge at work which measures airflow so might try to connect that up, It's probably not as bad as I thought it was if 10-15 litres per minute is normal.

Re the valve stem seals, If I remove the camshaft will I then be able to use the Collette removal tool?

Thanks again

jontee61 · Oct 5, 2015

Homer123s said:
I'll check the hose tomorrow, might have a gauge at work which measures airflow so might try to connect that up, It's probably not as bad as I thought it was if 10-15 litres per minute is normal.

Re the valve stem seals, If I remove the camshaft will I then be able to use the Collette removal tool?

Thanks again

're removal tool as I understand it is a specialist price of equipment it makes removal of the coollet simple and easy BUT you may not be able to purchase one as the only seem available to purchase in USA but a competent garage should be able to do it for you or use the compressed air method as already suggested as long as you do one valve at a time but make sure you can purchase correct seals before dissembling . Alternatively have you tried using engine seal rejuvenation additive. which can be bought at any good motorist shop. You put it into you engine oil then run as normal best results take for long run can take up to 200miles for treatment to work completely but rejuvenated ALL the oil seals in the engine I have used it many times on various vehicles with positive results every time.. on present van 2-5 rd had leak from crankshaft seal. One an half tins of additive. No leak. !!!!! Should work on valve seals. Anyway worth a shot.jt

Homer123s · Oct 6, 2015

jontee61 said:
're removal tool as I understand it is a specialist price of equipment it makes removal of the coollet simple and easy BUT you may not be able to purchase one as the only seem available to purchase in USA but a competent garage should be able to do it for you or use the compressed air method as already suggested as long as you do one valve at a time but make sure you can purchase correct seals before dissembling . Alternatively have you tried using engine seal rejuvenation additive. which can be bought at any good motorist shop. You put it into you engine oil then run as normal best results take for long run can take up to 200miles for treatment to work completely but rejuvenated ALL the oil seals in the engine I have used it many times on various vehicles with positive results every time.. on present van 2-5 rd had leak from crankshaft seal. One an half tins of additive. No leak. !!!!! Should work on valve seals. Anyway worth a shot.jt

Think I might try some additive first, its not expensive and definitely worth a try. Any suggestion which type to use, I've seen both Wynn's and Forte recommended.

Haven't tried air flow yet but did check hose yesterday, its not kinked but is open ended, should this be connected in anywhere?

corcai · Oct 6, 2015

Homer123s said:
Think I might try some additive first, its not expensive and definitely worth a try. Any suggestion which type to use, I've seen both Wynn's and Forte recommended.

Haven't tried air flow yet but did check hose yesterday, its not kinked but is open ended, should this be connected in anywhere?

Breather normally goes to the intake somewhere on the engine side of the air filter. Check the air filter housing for a spigot the appropriate size. If the hose has been off it will have been drawing unfiltered air through the spigot.

jontee61 · Oct 7, 2015

corcai said:
Breather normally goes to the intake somewhere on the engine side of the air filter. Check the air filter housing for a spigot the appropriate size. If the hose has been off it will have been drawing unfiltered air through the spigot.

Hi 're additive I don't think it would make great difference which one used One tin would be recommended but I have used two tins in the past with no ill effects. Just give it time to work the more miles the better. Fingers crossed. Jt

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