Cylinder Head D24 vs D24T
 

Hello
Currently I swap D24T to my Volvo 245 USA 84' Engine from Volvo 940 92', today I took off a cylinder head and on each cylinder are cracks between the valves :( Before removing the head I measured the pressure and on each was 32 ​​bar, so very good.
I have original cylinder head from my 245 D24. Whether the head of the D24 will be matched to the D24T ? Maybe I can swap valves from d24t head to d24 and it will be working ?

Cracks between the valve seats are considered OK as long as they are less than a certain size. The greenbook gives a spec for maximum acceptable width but generally as long as it is small enough that you can't fit your fingernail in it, the head is considered OK.

Those cracks are very common... I bet that if you pull the head off your D24 there is a good chance you will find it has some cracks too. No big deal if they're within limits -- the motor won't know the difference!

Head of D24 i have already removed and there aren't any cracks :) My D24 have crank mechanism in bad condition, pressure:
1 - 28, 2 - 19, 3 - 19, 4 - 24, 5 - 22, 6 - 17
So I decided to swap D24T

There are pics of cracks (1-6 cylinders)
http://imageshack.us/a/img96/8162/d6oq.jpg
http://imageshack.us/a/img854/2931/b9ay.jpg
http://imageshack.us/a/img547/6726/9y9s.jpg
http://imageshack.us/a/img27/9158/fuli.jpg
http://imageshack.us/a/img809/2301/blqa.jpg
http://imageshack.us/a/img17/2930/aga9.jpg

What do you think about that and that vertical cracks on 2,3,4,5 cylinders ? How to prevent these cracks aren't expanded ?

they got that motor so hot it wold not turn anymore , maybe afew times is my guess.

Those vertical cracks are fatal. There is a guy on TDIclub who can fix that, but it won't be worth the $ unless you have thousands invested in porting and whatnot.

Thanks guys, so I must search new head :( find one in good condition is almost impossible :rolleyes:
I need to buy cylinder head from d24t, beacuse from d24 doesn't fit ? how can I distinguish head from d24 and d24t ?

T has 12 mm head bolts, 11mm for D24. Somebody on here recently got a new one from a company in Spain or Portugal.

Those cracks are pretty bad.

D24 has 12mm head bolts same as D24T, only very early D24's had 11mm (1979-1980). You can tell the difference, 11mm bolts have inhex head, 12mm has triple square head. I have never seen an 11mm D24 in the flesh, though theoretically they do exist... I have only ever seen 11mm bolts on old 1.5 VW's.

A 12mm D24 head can bolt right onto D24T, there are only a couple of functional differences, D24 has a narrower vacuum pump push rod bore (14mm instead of 16mm) so you need to keep the pushrod with the head, and D24 does not have the right-angle coolant nipple on the back of the head for the oil cooler connection; however, it does have a freeze plug back there that you can knock out, then you just have to drill and tap a bolt hole for the securing flange and transfer the nipple over from your turbo head.

Or, you can take advantage of it already being blocked off, install a freeze plug to block off the other end of that circuit (at top of thermostat housing), and eliminate the stock oil heat exchanger as a number of people have done. Can either run without it (if not going crazy with boost/fuel/egt and not doing a lot of hills in hot weather), or can retrofit a different oil cooler setup, a few different options there.

The D24T head is technically supposed to also have some less obvious differences in terms of casting material, valves, etc, maybe valve seats too. Realistically the NA head will work just fine at stock power level and probably even well beyond it, long as you don't overheat it, which you can't do anyway regardless of what head you have on it. ;) If the NA head is in good shape I would probably just bolt it on.

However, I also agree that if that turbo head got cracked that badly the whole motor must have gotten pretty hot -- I would check it thoroughly while you already have it this far apart and make sure the bottom end didn't get hurt. Usually when there is that much heat you see bore and piston damage as well. You said the compression results were good so maybe it got lucky, but I would look carefully for any signs of scoring in the cylinder bores, etc. Now would be an easier time to fix that than later...!

Good, n/a head goes to the grinder for a complete overhaul, new valve seats, valves, etc. Ofcourse I look at crank mechanism, take off the oil pan and watch the crank and shafts.
Thanks again :)

Sorry, I misunderstood, and thought you had stated that your head did not fit.

Some may not agree with me, but I'd avoid having the prechambers installed when surfacing the head, they are supposed to stick out 0.001 or so.
Valve face depth below the head surface should also be set within spec.
A turbo head should have better sodium filled exhaust valves.

One of the first things that happens with these things running hot is the rings lose their temper, and don't push aginst the walls right. This gives you a car that smokes all the time or off boost even if the rings don't seem too worn.

I am running a D24 head on a D24T that I am running in an 83 245. I did replace all of the valves, and had it re-surfaced with the pre-chambers still installed. I probably have over a 100K miles on on it since the overhaul. (The odometer gave up the ghost) I have a 200 mile commute weekdays. The pump is at stock settings .95 on the IP timing and the turbo set at 20 psi max boost.