P38A How i fixed my German problem - How not to use timing tools

Hello All,

So if you saw my other threads i recently embarked on a European road trip in a newly acquired P38 2.5 Diesel.

It ended in a mild engine bay explosion in which the bottom of the radiator fell out of love with the rest of the car and ejected itself although i think we pulled over fast enough to not do any damage, i mean water was still pouring out when we stopped.

After overnight parts from paddock and some great camp-site car park spannering she was back in order... so we thought. Started up and the coolant was emptied in 200m worth of driving, hmm big of a larger issue then just a bit of overheating.

So after calling in many favours we managed to get the beast back to the UK and started the repair job. The first task, stripping down the head and seeing how bad a situation we were dealing with. Hoping for a simple head gasket failure; we pulled of the head to find a very good condition gasket and block/cylinder/pistons... turning the head over however revealed the culprit. A monster crack going from the injector port through the center of the valves. There were also 3 other cylinders showing this crack starting.

The search for a new head was on, which was far more of a task then we first expected. Numerous offers for complete engines from the usually internet based bidding websites however very few people selling the heads, and those that were; were asking far to much. Then luckily found a nice 525 TDS at a "pick your own" parts yard. So the next saturday me and the other 2 owners of the range spent the morning stripping down a 80k auto 525 TDS (hopefully being a nice light 5 series and an auto it should have had an easy life). The complete head, including injectors, plugs, etc etc was £120. Not bad.

Now on to the rebuild and realising the mistake we made by being tight and not buying the timing tools. When we dismantled the engine we didn't have the timing tools but we got it to TDC and thought we would be ok, until we took the camshaft sprocket off and realised we need them to locate it back on.

Luckily this forum came into its own and Grrrrrrrrrrrrrrrrrrrrrrr (Unknown number of r's) AKA Jules was kind enough to lend us his tools. Now we cant mess it up... can we?

The car is fully back together and all that is left to do is bleed the high pressure lines and let her warm up to do the final bolt tightening. No matter how many times we bled her she would not start. Now we did chuck in a bit of easy start to see if there was a fuel problem and she ran on that. So whats going on? we thought there was still air in the fuel so continued bleeding and bleeding the lines. Until suddenly it hit me... there is a way you can use the timing tools and still get it wrong. You can have the cam locked and the flywheel locked and the camshaft and fuel pump be 180 degs out from each other. And that is what we had done. So quickly undid the cam sprocket, turned the crank a sixth of a rotation so all the pistons were level as to not conflict with the valves and then turn the cam round 180 deg. Tightened it all up and boom she was running away.

So that's how i managed to get timing tools wrong.

Anthony Day said:

Hello All,

So if you saw my other threads i recently embarked on a European road trip in a newly acquired P38 2.5 Diesel.

It ended in a mild engine bay explosion in which the bottom of the radiator fell out of love with the rest of the car and ejected itself although i think we pulled over fast enough to not do any damage, i mean water was still pouring out when we stopped.

After overnight parts from paddock and some great camp-site car park spannering she was back in order... so we thought. Started up and the coolant was emptied in 200m worth of driving, hmm big of a larger issue then just a bit of overheating.

So after calling in many favours we managed to get the beast back to the UK and started the repair job. The first task, stripping down the head and seeing how bad a situation we were dealing with. Hoping for a simple head gasket failure; we pulled of the head to find a very good condition gasket and block/cylinder/pistons... turning the head over however revealed the culprit. A monster crack going from the injector port through the center of the valves. There were also 3 other cylinders showing this crack starting.

The search for a new head was on, which was far more of a task then we first expected. Numerous offers for complete engines from the usually internet based bidding websites however very few people selling the heads, and those that were; were asking far to much. Then luckily found a nice 525 TDS at a "pick your own" parts yard. So the next saturday me and the other 2 owners of the range spent the morning stripping down a 80k auto 525 TDS (hopefully being a nice light 5 series and an auto it should have had an easy life). The complete head, including injectors, plugs, etc etc was £120. Not bad.

Now on to the rebuild and realising the mistake we made by being tight and not buying the timing tools. When we dismantled the engine we didn't have the timing tools but we got it to TDC and thought we would be ok, until we took the camshaft sprocket off and realised we need them to locate it back on.

Luckily this forum came into its own and Grrrrrrrrrrrrrrrrrrrrrrr (Unknown number of r's) AKA Jules was kind enough to lend us his tools. Now we cant mess it up... can we?

The car is fully back together and all that is left to do is bleed the high pressure lines and let her warm up to do the final bolt tightening. No matter how many times we bled her she would not start. Now we did chuck in a bit of easy start to see if there was a fuel problem and she ran on that. So whats going on? we thought there was still air in the fuel so continued bleeding and bleeding the lines. Until suddenly it hit me... there is a way you can use the timing tools and still get it wrong. You can have the cam locked and the flywheel locked and the camshaft and fuel pump be 180 degs out from each other. And that is what we had done. So quickly undid the cam sprocket, turned the crank a sixth of a rotation so all the pistons were level as to not conflict with the valves and then turn the cam round 180 deg. Tightened it all up and boom she was running away.

So that's how i managed to get timing tools wrong.

Click to expand...

No you managed to lock the cam in the wrong place with the timing tool.

Nah, it was locked with the lobes pointing up. What had happened is the crank got turned over 360 so the pin still went in but now the pump was 180 out from the cam.

Anthony Day said:

Nah, it was locked with the lobes pointing up. What had happened is the crank got turned over 360 so the pin still went in but now the pump was 180 out from the cam.

Click to expand...

Crank should have been locked at TDC number one firing before you started work. But if you turn engine to clean piston crowns, from TDC you need to remember number one down up down up = TDC.

Ah, well done for owing up! And even better, spotting it! Let's hope that's the end of your issues.

Yeah it was a bit of a red face moment but no damage was done so on to the next thing.