87 ECM, LT1 MAF & Translator Upgrades - Before and After

[BroadcastENG]

Check you couplers first but it does sound like you lifted a head enough to do damage to the gasket.

Pronto: which couplers are you talking about? Vacuum line couplers?

 

[SCOOBY DOO]

Couplers for the up pipe will blow off occasionally.

 

[SCOOBY DOO]

I'd get the heads skimmed and freshened up...but that's just me.

 

[Pronto]

Pronto: which couplers are you talking about? Vacuum line couplers?

The charge pipes.

 

[BroadcastENG]

I'd get the heads skimmed and freshened up...but that's just me.

Would this include valve spring replacement?

 

[Pronto]

This may have been slowly happing before you did the 87 ecm upgrade. I would have them check the spring pressures while you're there.

 

[BroadcastENG]

This may have been slowly happing before you did the 87 ecm upgrade. I would have them check the spring pressures while you're there.

I understand that not all auto mechanics are familiar with our turbo 6 engines but any machine shop should be able to take care of the head refresh, right?

 

[SCOOBY DOO]

I understand that not all auto mechanics are familiar with our turbo 6 engines but any machine shop should be able to take care of the head refresh, right?

Get someone to recommend a machine shop in your area.

 

[BroadcastENG]

Get someone to recommend a machine shop in your area.

Working on it!

 

[Pronto]

While you're at it you should have your injectors cleaned. It's possible they are clogged and caused the rough running etc and lead to the lean out.

 

[BroadcastENG]

While you're at it you should have your injectors cleaned. It's possible they are clogged and caused the rough running etc and lead to the lean out.

I had the injectors serviced when I replaced my intake gasket, prior to getting the car on the road full time. I can have them flow tested just in case.

 

[BroadcastENG]

Weekend warrior update: I pulled the heads off over the last couple of days and have a two machine shops I plan to visit before the end of the week.

In addition to having the spring pressure checked and minimal decking (so I can use stock pushrods and rocker assembly), I've read (on this forum) that a three angle profile for the valve seats is recommended when your heads are out for a refresh. Maybe this is already included in the "standard" machine shop refresh procedure but I wanted to ask here rather than make the assumption.

I found no broken or bent (table top roll test pending) pushrods but some wear at the top/tip of a few valve stems tips on the drivers side. I did notice a rocker shaft bolt (drivers side) that wasn't as tight as the others (bolt closets to front of block) that could be the cause of the vavle tip wear. The rocker shaft assembly looks to be in good shape and if the pushrods are straight, should I reuse?

I did not find a gasket blowout like I had envisioned and seen online but more of a dark spot on the topside of the gasket (9 o'clock) for cylinder 4. Maybe this is the point of failure and that's why I had 0 PSI for my cylinder 4 compression test.

With the lower half of the engine exposed I plan on cleaning up the head mating surfaces and around the outside of the block. What about the piston tops/crown? Should I take a brillo pad and degreaser to them?

The oil pan will be removed this weekend. I will clean as best as I can and will install a cork gasket with the right stuff and original bolts. With the exhaust manifolds/crossover removed, now should be a good time to replace the rear main seal (oil on starter, bell housing cover, crossover pipe midpoint), right?

Last but not least, how many more bolts would I need to remove to just pull the block out at this point?


Thanks in advance.

 

[Pronto]

It would be a lot easier if you just pulled the block.

 

[BroadcastENG]

It would be a lot easier if you just pulled the block.

At this point I see that there is not much left to remove. I dig into my manual tonight and will identify the last remaining bolts to remove.

 

[BroadcastENG]

Update # 2: I pulled the block and have gotten as far as removing the oil pan and timing cover. I found a sleeved cylinder (4) and a upgraded timing set with no oil slinger. Attaching pictures to show sleeved cylinder and timing sprocket wear (is the wear pattern normal?)

My freshened up heads (reports of couple of bent valves but I did not see any contact points in the piston head/crowns) will be picked up from the machine shop early next week and in the meantime I will be cleaning up and reinstalling the timing cover, checking the bearings for wear, and replacing the rear main seal.

 

[SCOOBY DOO]

Clean off one of the tops of the pistons and find out if its STD or over bore. Put the slinger back on...it's there for a reason. I'd go with a new timing chain set with the wear I'm seeing.

 

[BroadcastENG]

Clean off one of the tops of the pistons and find out if its STD or over bore. Put the slinger back on...it's there for a reason. I'd go with a new timing chain set with the wear I'm seeing.

Good copy: New timing set on my shelf, just waiting on the damper from RA. Oil slinger on order. The lifters & cam (lifter to cam) contact surfaces show no pitting or signs of distress. Will reuse rocker assembly (new buttons?), pushrods and lifters.

 

[SCOOBY DOO]

Make sure the lifters go in the same holes. Lots of break in lube on the mating surfaces. Run the pushrods on glass to check for straight. I always made sure the rockers were marked for DS and PS. Inspect the rockers for cracks.

 

[BroadcastENG]

Push rods, lifters and rocker assemblies organized to go back in as they went in (mell-lube). Will roll the pushrods on glass tonight. Thanks!

 

[BroadcastENG]

Update # 3: The timing chain set was replaced, push rods rolled true, timing cover work included new oil pump gears that were replaced and a new oil pump cover was installed. .008 gasket gets me .003 clearance (plastigauge) with the gears moving easily without any effort. Are the oil cover gaskets available in .007 or is there a .001 that I can add to an existing. 006? If there is I'd bet I could get to .002 top clearance.

Cover carbon buildup was removed from the piston tops; over bore (piston heads (30) and oil pan mating surfaces (030 / 005) stamped. Next step: confirm over bore.

I bought a bore gauge to double-check. 0'd the bore gauge using digital caliper set to 3.791. No reading from the larger cylinder hole. I got confused and proceeded with 0 ing out the bore gauge in cylinder, then I took the bore gauge to the digital caliper. I sampled 1-point (thrust side) for each cylinder and measured 3.8115 . Not the way I saw someone perform this task online but it's where I ended up last night.

Thanks