Thread: urgent td5 head advice please!!!

Originally Posted by Rosscoe68

sorry to thread steal.
dropped my head off today, they reckon it will need about 15-20 thou to take the head gasket ridge away, but assured me that the head hardness is good still.
the head is pressure tested and holds no probs, and there is obvious signs that the gasket itself was leaking thus the blown headgasket fault, not a cracked head.

is this too much to take off ?
they will only do it if i agree for them to reseat the valves to compensate for the valve/piston clearance, which i agree is fine, but just not sure if thats too much to take off the head

Wow and i was concerned with 9 thou. In this situation you would think there would be a valve to piston problem if not dealt with. Hope it works out rosco.

Originally Posted by jimbob

Did the head kill its self or the turbo?? This is the first td5 head i have heard of being welded and 100 000 ks well worth it.

It would have been one of the few. At the time eveyone told me it couldn't welded and I was up for a new head. It took 40,000km of ownership to confirm all my problems were the head.
Quotes for a new head ranged from $2-5 grand where it cost me $800 for it to be welded, skimed, valves reseated and custome valve washers made for it (Done through a mate so I had to let the machinist have it for 2 months or he would have charged full rates for the work).

Final death of the engine was due to chronic blow by believed to be carbon in the rings. Treatments arrived in the post the day after it blew.

I was heading up a big hill on the freeway when I noticed the oil pressure guage was not reading much if anything. Then black smoke and steam billowing out of the bonnet and up through the transmission. As soon as I hit the indicator and lifted my foot of the go peddle to role to the side every alarm and dash light went off and the engine stopped dead. I pulled over to see the fire in the bonnet linning go out and the last of the oil and coolent drip from everything. The next day after it was towwed she was seased. Still havn't polled the old engine down yet for a full list of damage. I know the turbo wasy gate was totaly jammed and twisted and no seals left in it so new engine and turbo now live under the hood. I had filled the oil only the day before due to losses.

We still think the head is ok.

I've just been through a TD5 head reconditioning myself. I think I've read the entire thread and believe further advice should help.

Firstly I think hardness is a bit of a furphy - nothing is supposed to hit the head so surface hardness, and I mean SURFACE hardness, shouldn't effect performance much at all - or so I reckon.

Secondly, the valve recess (or stand down) is given in the RAVE manual: inlet 0.555 - 0.825mm and exhaust 0.545 - 1.35mm. Easily checked with strait edge and feeler gauges.

Lastly, I wouldn't rely on what was there before to determine the head gasket to use. If without a DTI just lay a strait edge over the piston at top dead centre and using feeler gauges measure gaps to block both sides of the piston. Keep the largest. Repeat for all pistons. Then choose the head gasket according to the manual: protrusion 0.351 - 0.500 = 2 hole; 0.501 - 0.570 = 1 hole; and 0.571 - 0.650 = 3 hole.

If it's not to late best wishes ...

ps - mine had 1 hole and after head and block shave a 2 hole suited!!! maybe the 50 thou' oversize pistons were a nouce lower or ... who knows ... attention to details huh.

The worst of it for me was when I came to tightening up the new head bolts and finding the threads were filthy an f...ed. I had to rip the head off again and find a long tap handle to get down and clean them up.

Originally Posted by canblogerra

I've just been through a TD5 head reconditioning myself. I think I've read the entire thread and believe further advice should help.

Firstly I think hardness is a bit of a furphy - nothing is supposed to hit the head so surface hardness, and I mean SURFACE hardness, shouldn't effect performance much at all - or so I reckon.

Secondly, the valve recess (or stand down) is given in the RAVE manual: inlet 0.555 - 0.825mm and exhaust 0.545 - 1.35mm. Easily checked with strait edge and feeler gauges.

Lastly, I wouldn't rely on what was there before to determine the head gasket to use. If without a DTI just lay a strait edge over the piston at top dead centre and using feeler gauges measure gaps to block both sides of the piston. Keep the largest. Repeat for all pistons. Then choose the head gasket according to the manual: protrusion 0.351 - 0.500 = 2 hole; 0.501 - 0.570 = 1 hole; and 0.571 - 0.650 = 3 hole.

If it's not to late best wishes ...

ps - mine had 1 hole and after head and block shave a 2 hole suited!!! maybe the 50 thou' oversize pistons were a nouce lower or ... who knows ... attention to details huh.

The worst of it for me was when I came to tightening up the new head bolts and finding the threads were filthy an f...ed. I had to rip the head off again and find a long tap handle to get down and clean them up.

Yes that is exactly what i was planning. Back into it today. Fingers crossed.

One more question, What is the head bolt sequence for a TD5? Cant seem to find it on rave or on here. Any one know what the sequence is??

Sequence as in torque or order?

Torque is

30Nm
65Nm
then a further 90 degrees
then a further 180 degrees
then a further 45 degrees

Order is

Drivers side: ....10 / 6 / 2 / 3 / 7 / 11
front of engine
Passenger side: 9 / 5 / 1 / 4 / 8 / 12

Edited to add this - may be easier:

Thanks every one for all your help. The car was up and running on sun morning. Started up fine but on the first test drive temp climbed very quickly once at operating temp. So the temp was climbing normally up untill about 85 deg then shot up to 97 real fast. I am wondering if it has a cracked head that only opens up and leaks once the head is hot?? Not sure what else to do. Radiator has been out and checked by radiator place. The only two things that have any thing to do with the cooling system that have not been replaced is the water pump and the oil cooler. I dont think these would cause air to get into the cooling system witch I think is happening but not sure because these are a pig to bleed.

I think i will replace the water pump just as a process of ellimination. Then i guess its a new head OUCH!!

Any ones thoughts or ideas would be greatly appreciated.

Cheers Jim

Hi Jim,

I would certainly look at the waterpump (there have been cases where the impeller has mostly gone), and also possibly the thermostat if you haven't already done it.

How are you reading the temperature that accurately?

Rgds
Peter