85 911 Cab... no clue what to ask

[Rick Brooklyn]

I think you totally did the right thing to hold on to your ask. A 3.2 that runs under its own power and isn't falling to pieces from rust is worth more than $30k.

[airkewldfan]

Sorry to hear that and hope it’s not too bad

[Rawknees'Turbo]

Originally Posted by cabmando

Well... it's off the market for now. I was driving it the other day and somehow managed to do a 1/2/1 shift at 60 mph. Engine is going to come out and get taken down to inspect and see what needs replaced.

I have no idea how I hit first coming out of second. I have the seine gate shift kit that centers in the 3/4 shift plane. I pushed it out of 2nd with my palm and grabbed the shifter to go into 3rd. I didn't put any pressure to the left but somehow I still ended up in first. F..k! I'm ready for 2021 to be over with.

Too bad there wasn't a 930 box in your car, as you can easily do 70MPH in first in that bisch (can safely backshift from 4th to 3rd at 130mph in 4th even, according to the owner's manual). Of course you need some actual pooowwwaaaahhhh in order to use a 930 box to begin with, however!

In fact, Nick, I think the mysterious shifting error is your Cab's way of telling you, "Hey bisch, build a boosted engine for me so I can be a real car like that fat assed, hardtop version of me in TexASS, bisch!"!

[cabmandone]

The funny thing about this is my old transmission never would have let me go into 1! You'd feel it in the shifter the moment you tried because you'd be grinding the dog teeth. I couldn't go into 1 with my old transmission unless I was at a complete stop. I'm missing my old transmission right about now.

I'm going to get into some troubleshooting to see what's going on with the #4 cylinder. It's the only one that wasn't heating up. The rest were all pretty close as far as exhaust port temps. I'm probably going to drain the oil today and drop the valve covers on the right side to see if there's anything visibly wrong with #4. I saw something on the piston that was cleaner than the rest that gave me a reason for concern. I have to wait on an extension tube to arrive before I get into a leak down test. The engine guys I've talked to suggest a compression test but I really don't want to let the engine run to warm up until I'm sure the top end is okay.

[matt930s]

Yeah, get a visual first and post pics (of your engine too)…

[cabmandone]

Can't post pics. My bore scope isn't the best. I have a thread going in the tech section but I'll update here as well.
I have a smile that is evident on 4 out of 6 cylinders. I'm going to drain the oil, pull the valve covers and turn the engine over by hand while watching the valves. I should be able to put the engine at #1 tdc and go around like I'm doing a valve adjustment. If any are loose that would indicate either a collapsed spring or a bent valve. I'd just need to confirm which it is if I find one or more that are loose.

Update:
I drained the oil and pulled the valve covers. I put the engine to #1 TDC and hand checked the play. I turned the engine 120... checked 6, 120.. checked 2.. and so on. #4 exhaust felt loose. I'm not sure if it is loose enough to keep the cylinder from firing (#4 was the cold cylinder). I'm going to rotate back to #4 and check with my feeler gauges. I just set the valves in the spring when I installed the refreshed transmission so they should still be good but the exhaust felt loose which would indicate a bent valve.

[cabmandone]

Update:
Leak down confirms #4. #1 is bad as well but nothing close to as bad as #4. 2&6 were pretty solid at 5% leak down. I stopped when I saw how bad #4 was. I'm talking 80 psi on the inlet side and 30 psi on the pressure side.

I'm planning to drop the engine next week sometime and start disassembling. My brother is planning a trip home in October so he'll bring his engine stand yoke and specialty tools. Once I've got it disassembled, I'll be taking the heads to cgarr. Then it's just a waiting game and deciding whether to replace the pistons.

[911heaven]

Sorry to hear the news N2! Sh-t happens at times in life, yet one has to roll with it and get beyond it. I can see you have a special knack for that! Looking forward to when you got the cab all back to her optimum shape. Shouldn't be long I'd say with your knowledge and skill.

bernie

[cabmandone]

Sh.t does indeed happen Berns. Yeah I'm over it. I was REALLY pissed when it happened because of how it happened. But life goes on. It's funny, the main reason I was trying to sell was because I was tired of working on cars. I told my brother I didn't have the love for the car to put money in it if something happened to the engine. Now I don't have a choice if I want to sell it.

It's kind of a shame really. Cylinders 1,4 and 6 all leaked. 2,3,5 still had REALLY good leakdown numbers.. around 5% or less. This engine used to be pretty solid! I should have done the leak down sooner. It probably would have sold if I had.

[911heaven]

Originally Posted by cabmando

Sh.t does indeed happen Berns. Yeah I'm over it. I was REALLY pissed when it happened because of how it happened. But life goes on. It's funny, the main reason I was trying to sell was because I was tired of working on cars. I told my brother I didn't have the love for the car to put money in it if something happened to the engine. Now I don't have a choice if I want to sell it.

It's kind of a shame really. Cylinders 1,4 and 6 all leaked. 2,3,5 still had REALLY good leakdown numbers.. around 5% or less. This engine used to be pretty solid! I should have done the leak down sooner. It probably would have sold if I had.

Here's a thought. Keep it in the family! Give it to all three kids to share, drive and work on. They can all drive it, work on it and enjoy it under your supervision. The bonus? You can also drive and enjoy it with or without them individually! Whomever does the most household chores gets first spin so to speak... that is if you don't need the 30-40K in your pocket. When the kids leave the nest, you might even sell and then at 100K perhaps.

[cabmandone]

I told my pistons to smile for the camera!
The weird thing is, the clean spot on the exhaust valves doesn't correspond to the "smile" on the piston. Do valves rotate when the engine is running?

[Matt Monson]

Only if they are bent.

[David Borden]

Whats the plan to fix? New Valves and put her back together or going deeper?

[cabmandone]

Originally Posted by David Borden

Whats the plan to fix? New Valves and put her back together or going deeper?

With the leak down numbers on the other cylinders being around 5% I'm leaning towards doing the top end and putting it back together. Without my paper in front of me, I think it was 1,4, & 6 that had poor leak down numbers with 2,3 & 5 having around 5% The cylinders look good and the crosshatching is still obvious. I think what will make the call for me is cleaning the piston tops and seeing what kind of a dent is really there. I've read plenty of threads where guys say "just buff the piston tops and put it back together".

It's really surprising how small the gap needs to be to really let air past. I can tell #4 exhaust valve is just barely open but on leak down, just barely means 90 psi in and it won't build over 40 psi due to a slight gap in the valve and seat.

[cabmandone]

Here's 4,5,6 You can see the smile on #4 clearly. It's the only dead cylinder and by far the worst from the leak down test. I'm currently consulting with some of the engine guys about what to do going forward. I have a set of pistons that only have about 20K on them that I could install but I'm not sure how great an idea that is. I'm currently removing carbon from the piston tops. I'm hoping once clean that'll give me a better idea what kind of damage there is to the piston. I think the carbon makes it look a lot worse than it really is.

[Mocker]

Did you know previously that your heads weren't all original (different manufacturing dates)?

[Matt Monson]

Originally Posted by Mocker

Did you know previously that your heads weren't all original (different manufacturing dates)?

That’s a falsehood that’s been thrown around this board for years. I’ve seen dozens of known original engines torn down, sometimes with casting dates 6 months apart.

[Mocker]

1-86 and 11-83, tho?

[Mocker]

Oh, I see--that's 1-84. My bad.

[Matt Monson]

No worries. My eyes are going too, and this stupid little phone doesn’t help me in that dept.