We all have different opinions but this repair will be a complete disappointment unless there is a complete rebuild. Many times an engine is over heated, there are more than just the heads that are warped. That engine looks to be nothing better than scrap iron. Of course, it's just an opinion. You could invest a lot of time and effort to resurrect this, but it's going to take a lot of money to do it right. The more corners you cut, the worst the outcome will be.

I would go about this repair different. I would get a good core engine, rebuild that [properly, complete machining] and make a swap.

 

G'day, buddy.

There'd be no room to use a hoist, and even if I could get the engine out, I'd have to wrestle it back over my truck and up my driveway. Not an option to be lightly undertaken by a 77 year old bloke with rheumatism...!

I'll wait to hear what the engineering shop says before I think about anything like that.

Oh, and re the Felpro high tolerance gaskets, all I remember was a figure of eighty something or other...

 

Hi, 1Butcher.

Thanks kindly for your comment, and I don't doubt you're far better informed than me, so no disrespect intended, but at the moment I don't feel I can go that way, for a number of reasons that have little to do with matters mechanical.

 

I don't know your driveway layout, and sorry about your physical condition. (I'm 64, a little more spritely, but not exactly in my prime either.)

Definitely take some measurements on the block to check for warpage. That should tell you whether the high tolerance gaskets will work. If not, then you probably do need to have the block decked, which means pulling it to bring to the machinist.

I usually put the engine on an engine stand as soon as I pull it out of the vehicle. It's much easier to move the engine around on the stand (with casters) than on the hoist. You might want to enlist the assistance of younger and stronger blokes for this.

 

Could be worse...I'd beaten bladder cancer and chemo seven years ago, and had got back to being able to get a load of firewood in a day and not a hint of issues with my joints, and then along came Covid and those damned vaccines...and suddenly I'm an old man. Sucks...

Anyways, the advice I've received here has had an impact, even on bull headed yours truly. Ultimate fall back position is that I get the old girl towed to the garage and go for an engine transplant. It'll cost a fortune, and I don't even know if I can find a towie to take it on (steep narrow driveway, BIG truck). There's still a load of firewood on the back too, which I'll have to get off and dump at the front.

So I'm not going to send the heads to the engineering shop straight away. Why throw good money after bad...if it is bad, that is.

First I'm going to check the block and heads for warpage and cracks as best I can, pull a couple of valves and have a look at them, and of course post photos here so I can get feedback. I'm also going to rotate the engine by hand and measure the height of the pistons at top dead centre, as I've heard you do that to get some idea if the crankshaft has warped.

Bit of an adventure, eh?

 

Still going through my own adventure day by day:

https://photos.google.com/share/AF1Q...Zycm5RNTZTeWZB

I should post this in the Aerostar forum.

 

Awesome! Not an adventure...more an epic.

 

Righto, I've got the valves out, and could use some feedback, as it all looks a right mess. I'm guessing the buildup on the sample valve in the pictures (all inlet valves have similar or worse buildup) is blow back doing the circuit from sump via the PCV valve to inlet manifold? What should I be expecting the engineering workshop to want to do?





left side head before cleanup

left side head before cleanup

 

With the life that your engine has gone through, I would have them do full overhaul. This includes valve jobs on both heads, which will include at least:

check for cracks to see if the heads are usable

cleaning up the valves: grinding the valve faces with a 3-angle cut

matching cuts on the valve seats

replace valve guides

new valve springs

milling the heads flat and true

The valve build up you showed are indicative of much cylinder blow-by collected by the PCV, so the cylinders are probably pretty worn. Do you see factory cross-hatching on the walls?

I would also overhaul the block:

check for cracks to determine if the block is usable

bore the cylinders as needed

new pistons and rings to fit

new connecting rod bolts, re-fit the large end to the new bearings on the rod journals

new main, rod, and cam bearings

 

I'll get the engineering shop to give my heads the full work up, as you suggest. I haven't checked out the block and the cylinder walls closely yet, though I can see some scoring in the bore of one at least. Is it seriously technically demanding to hone the cylinders and replace the pistons? And could I at least leave it at that, and not do the bearings and bolts as well? This seems never ending...if I can get say 50,000 more miles out of her, that would probably see me done.

Thanks once more for your help.

 

To invest any money in this engine would be foolish until you have a really good idea what the list of repairs are. Freshly rebuilt heads on an engine with scored bores seems foolish.

If you were to remove the pistons, why would you not hone the bores and get new rings? I get that boring the engine will be costly, but if the bores are really scored and you are not going to address that, what is the purpose of rebuilding the heads?

 

When I was looking at my cracked head, I was considering just bolting on a new pair, until I saw the rust damage on the cylinder wall. The advice from others was if I did that, I would have serious blow-by in that cylinder, and cause more problems. So with over 170k miles on the engine, I decided that I would have it overhauled. When I remove the oil pan, I saw some amazing sludge on the bottom that I had not seen the last time I had to remove the pan to replace the gasket. I suspect this was due to all the blow-by mixed with coolant that got into the oil. So I'm glad I decided to have the short block rebuilt.

If your cylinders are not badly damaged, you might be able to get away with just putting the rebuilt heads on there, and it might last another 50,000 miles. But it could also decide to fail badly in other ways the next day, forcing you to do the overhaul anyway.

If you can drop the oil pan, you can get an assessment of the engine's condition, and that might help you decide.

 

Totally agree, so I've accepted now that the sump has to come off so I can hone the cylinders and replace the rings. Still trying to evaluate the block however, and I've found a hole in it next to the distributor assembly that I will post photos of today.

 

So here's the shots of the hole, plus a look down into the distributor well. Any thoughts, anyone?

Casting fault...?

Can't decide whether the bearing surface for the distributor shaft is broken, or machined that way to accommodate the cam gear. Also, what's that bell shaped thing next to the oil filter?

 

I think that hole inside the end rail is normal.

The boss that the distributor shaft goes through looks normal.

The bell shaped thing is the oil pressure sensor.