Welp,

It’s happened. Put some coolant dye in the coolant system to leak check the system. Lo and behold the back of my engine near 7 and 8 looks like a scene out of a Dexter episode. Coolant has been dripping out of the back. And due to the various shades of fluorescent green on the block, it looks like it has been occurring for a while.

Do I leak down and compression test before the heads are off?

If I do the head gaskets my plan is to drive it to my local muffler shop to replace the 6 exhaust manifolds right before I remove the heads so I don't have to roll around and struggle with seized rusted out bolts.


As well, to plan for the worst there is a short block available photo’d below and I contacted them asking if a pressure test had been done on the block and they indicated it had not been performed. Currently, it is listed for $1,300, however, without knowing if is another slipped sleeve or cracked block I think that is a steep price. The cylinders look sooty and not steem cleaned however, the second photo above cylinder 3 appears to have some interesting residue. I know these blocks cant be visually inspected for leaks but if I can get it for the right price maybe this would be a suitable option if I do indeed have a slipped liner or cracked block on top of my hg external leak?

 

If you want to do Leakdown and compression test then of course before disassembly is best. Sounds like you just have standard old age blown hg problem, nothing more serious so I would not assume it needs anything more than HG replacement. My lead the fleet vehicle currently has 260k on it running strong. If you do decide to replace engine completely I would look to source a good 4.0 block from as early a year as possible. I would contact Will Tillerey or Doc Heydary on facebook to get one, should be able to get a shortblock for less than a grand although maybe the market has increased recently. I know AB was buying every available 4.6 from breakers at premium prices. The option would be to source one from a wrecking yard, my normal advince is to look for one with significant body damage as that indicates it was likely running and driving decently at the time of collision - no guarantee but blown engines are not usually involved in accidents.

 

Good advice about the damaged vehicles.

As it turns out, I just found out about AB buying short blocks at a premium just now. I called the place where the photo’d short block was located and it turns out that depending on the condition AB is buying short blocks for $800-1200 from wreckers.

I took the D2 to a local shop to schedule a compression and leak down, but it really seems like a run of the mill external HG leak like you mentioned.

If it is the HG do I deck the heads? Is there a way to tell if they've been decked before? If they aren’t warped should I leave em?

 

The rave manual has the specs for checking head flatness, if they pass no need to deck them. If they don't, just have the shop take minimal material off.

 

Took the D2 to a shop to do a leak down, compression test, and verify the blown HG.

Confirmed HG external leak cylinder 7 and 8.

What’s the current preferred HG Kit to source?

 

Last time I did mine I bought the kit from Atlantic British.

my heads did need some machining and a broken valve spring replaced.

I’ve put about 180k on it since without issue

 

I also used AB for my head gaskets. I got arp head studs as well so it was a diy job I didn't need to use extensive maths or voodoo magic on to get proper torque.


I trued my heads up myself via concrete block... emergency situation over Christmas weekend 13 moths ago and still going strong.

Wouldn't recommend the block sanding method but would recommend the ARP head studs.