´74 Olds Delta 88 straight out of hibernation, troubleshooting and engine rebuild

Unleaded fuel was available before catalytic converters appeared in cars, for the 1975 model year.

I'd really like to see any documentation that any pre-75 car came with a catalytic converter

 

Vacuum gauge is steady at idle, and it idles fine once it started. Vacuum lines were the first thing I replaced, even before rebuilding the carb. There were so many vacuum leaks that spraying the throttle base and intake hardly made any difference. I won´t have time to tinker on before the weekend. I´ll just try driving it with a different muffler for a while and see what happens. I´m also gonna plug off the EGR line and see if that helps .
Thank you all for your ideas! I´ll work them all through.

 

And of course I´ll come back with updates on what I find. Promised!

 

Just to add some trouble some troubleshooting ammo, check the mechanical advance. It's under the rotor and easy to access on GM distributors. I have seen the old grease get hard, causing the advance to lockup when the engine warms up.

 

This brings up another check. Some after market rotors ribs on the bottom can rub/hit the advance plate and cause it to stick. Hits the pins I believe and an easy fix. Just use a dremel or something like it and grind a bit off the ribs till plate moves freely with rotor installed. .

 

Measure the exhaust back pressure.
Easiest way is making adapter plate in egr valve place.
Some cars have double layer exhaust pipes and inner tube can corrode and glogged.

 

Yes......once again.....look for the inner layer of a two layer exhaust pipe that has curled up and partially restricted exhaust flow. That was a problem in this era of GM cars.

 

Unleaded started before cats, which were 75.
To check the EGR, you can make a block off plate and bolt it on, Also, if it just runs up to temp without driving, the top of it should be fairly cool (no flow until ported vacuum is applied). It was a maintenance interval to remove the EGR and clean the pintle and seat. Rarely done, it can be checked by removing the EGR, turning it over and putting some liquid in the valve. It should not leak much or at all.

If vacuum routing is wrong, it could have manifold vacuum applied, but that alone shouldn't keep it from starting. You can check this by getting it up to temp and at idle, check for vacuum at the valve. It should not have vacuum at idle. The typical GM thermo vacuum valve had manifold vacuum, ported vacuum and the EGR hose. It would only apply vacuum to the EGR when warm.
https://www.ebay.com/itm/1975-Oldsm...FE-Valve-455-260-NOS-P-N-551472-/235499781935
A common 'fix' when these developed problems (or people hated the equipment) was to either plug the hose or if they were trying to sneak past the visual check install a small BB in the hose. We even had a term for it, the SSB223. Stainless Steel Ball 2 to 3 mm. You can obviously just remove the hose and plug it for testing.

I also suspect a plugged exhaust. If you are willing to risk it, loosen all exhaust manifold to pipe bolts and try it. This will also increase pressure at the EGR and can lift it up off it's seat.
You didn't say how long it has to sit to crank/no start when hot. If it's not time related, I'd lean toward vapor lock. If it happens after 5-10 minutes, these carbs tend to leak from the mid-section at the plugs, the 4 round areas sticking thru the gasket in this picture. This would also tend to long cranking times after sitting overnight, and you mention this is not an issue, so judge this yourself. The repair is to coat those 4 spots with JB weld. This one does not have the common staining when they do leak, but appears to be after cleaning.

1974 was the in start of the Malaise era. They had to keep adding things to meet emissions, so each year had different stuff and they were unique so parts combos weren't always sorted. There are intake gaskets that restrict the exhaust flow but that's for when all less invasive fixes have been tried.

 

The upper timing gear in those was plastic. I have seen those come apart with as little as 40,000 miles on them.

 

Ok, I ´ve been working on the car last night and today afternoon, and this is what I found out:
First thing, I checked the EGR valve for a vacuum leak. Well, it opened fully if I applied vaccuum, but couldn´t really hold it. I think the EGR was partly open most of the times and heated the manifold more than necessary. Plus it was a vacuum leak which didn´t help either.
Once this was fixed I only had to pump the accelerator once or twice to get a good hot start. So I turned out the idle mixtrure screw 4 1/2 revs instead of 2 1/2 and now it starts very nicely without even touching the gas pedal, even when hot.
I also removed both mufflers from the car, but none had any restrictions internally, even though the bigger one was quite baloooney.

But now it comes:
When I first tried to get this car to getto run right and played with the igntion I sometimes noticed a slight knock, just like one a sticky lifter or maybe slight detonation would cause. It went away when I hit the throttle and was gone during the test drives.
But today, on the last, longer test drive I suddenly heard the engine make a sound , pretty much like pinging, under acceleration, so I eased the car home. The hotter the oil got the more severely the knock became( the car has an oil temp gauge and an oil cooler, which may be part of the problem, but not sure yet). I removed the fuel pump to peak into the timing cover and check if the above mentioned plastic gear came apart, but the cam gear looks to be metal and brand new, no shrapnel to be seen anywhere. I also removed both valve covers , the engine is clean as a whistle inside and the valvtrain is tight and quiet. Using my earoscope and a long screwdriver I came to the conclusion the one of the front rod bearings are giving in. Tomorrow I´ll have to make a unpleasent call to Rudi.
here are two videos I took this afternoon.
https://youtube.com/shorts/7oGQNsgvaak?si=RCN6Cuu9_8_zAXbB
https://youtube.com/shorts/3xQ0Jnnd_DA?si=IdjftCbM5F-EqLNh
the sound quality of the second video is not that good, but it´s remarkable that the noise quietens down when the engine decelerates.

 

Here are the pics I took peaking inside the timing cover through the fuel pump mounting hole.

 

To be honest, I only had looked at these photos on my phone. Now looking at them on my computer screen, theres something looking kittywampus in the second photo. I know the olds´ have a deflector shim on the lower timing gear to avoid oil sloshing into the dampener seal... But this looks crooked somehow. Maybe the shiny, oily , flat surface mirrors something somehow...

 

Time to look for a 455.

 

Well...i actually have one disassembled 455 which needs new bearings and rings.
I also visit pretty often to travemünde harbour.
I could take it with me.

 

Thank you, @Pontmerc ! That is good to know! When @SS327 commented that it‘s time for a 455 my first thought was, were would I even look for one . But Rudi will have to decide the next steps, as this is not my car and I just offered to troubleshoot that bad starting and running issues for him at no charge. I can‘t spend that much time for an engine rebuild . My 34 rebuild is already taking forever , last thing I need is another project that is not even mine. But I will help and guide him through the rebuild and recommend him to my friend‘s machine shop. So I guess the story ends here for now at least!
Thank you all, your advice was highly appriciated , as always , and very helpful to get me on the right track. As usual it wasn‘t just one thing that was bad, and prior repair attempts didnt help a lot either hahahaha

 

https://www.pgbildelar.se/en/page/search-used-parts
They seems to have olds 350 in their stock.
This is a great place to go shopping if you have older american car.only place on earth, where i find pushbutton transmission for my turnpike cruiser

 

Here´s a last update. I pulled the timing cover and was able to move #1 rod with a long screwdriver. My friend also sold it to a new caretaker, he is coming to pick it up in 2 or 3 weeks. And I ran the numbers, it´s actually a 455 , not a 350. The new owner is going to get the crank ground and rods resized, other than that he just wants to cruise it, so the car is going to good home.

 

I guess I shouldn‘t have called it the final update last time. So, the person who wanted to pick up the car had to go to the hospital for an unforseeable period of time and backed out of the deal. Now Rudi offered it to me at a very low price . I think I‘m going to rebuild the engine, drive it for a while to see if it is reliable and eventually sell it and split the profits between Rudi and me. I already know he will refuse to accept any more money from me, but I will trick him out somehow
Next step, pulling the engine.

 

I must have missed it, what happened to the motor ?

 

rod knock

 

Turn the timing down and take it to the auction . lol

 

Well, I had nothing to do Saturday night, so I decided to pull the pan and see how bad the bearings and rod jouranal looks. I had a little hope I could get away with just polishing the journal and put in new bearings, but...no.



Engine had to come out, the #1 rod needs to be resized and the crank needs to be welded probably. I have not measured the journal yet, but there´s so much material gone I doubt grinding to .040 will be enough. I´d rather have it laser welded back to std. All other journal are perfect, also the bores are beautiful with no wear. The Odometer reads 51000 kms, I believe this might be true.

 

ouch

 

I just looked, Summit has a new eagle crank for an Olds 455, at 559$. If repairing the old crank will be close to this or more, I think I´ll order the new on from Summit. I sent a few photos to my machine shop guy, I´ll hurry up and wait what he has to say. I was also wondering if I shouldn´t replace the .320" dished piston with 442 ones, they only have a .120 dish and would come in at around 9.75:1 cr. This barge will never be a HotRod and I guess I won´t keep it for long. So that´d probably be just money thrown away..

 

I got a reply from a shop that specializes in Laser welding. He said it could be done, it would take 13 hours for the machine, as it was a really slow and cool process. He quoted me 1600 € for welding and 200€ for machining. I almost fell over backwards... So, good to know he is able to fix stuff that´s made out of unobtainium. But that´s not for this crank.

 

I also measured the amount of wear on the #1 journal. Well, the std journal size is 63,5 mm, at the lowest spot I measured 62,64mm which equals 0,86mm of wear. The most undersize rod bearing available is .040" / 1.016mm. Given the most wear occured on the upper side of the journal, .040 may just be enough to clean up. If that would be possible I´d just have the front main journal cut to .040 under and leave the other 3 std size. I can´t measure out of round good enough to make a decision, so the next thing on my list will be a trip to my machine shop buddy and see what he says.

 

You can always try what i do.
Nickel welding rods made just for cast iron and cold welding.so no need for pre heating.
Little pieces at time and lots of cooling time.
You got nothing to loose
https://shop.castolin.com/en-gb/cas...i34rQyidORFsuoB7QAW00sVGnan4Da5dBsef3s-kCUYKy

 

50K km is ~ 30K miles.
Original flat link/AL cam geared timing chain sets on Olds are usually pretty worn out by 30k miles.
Cam gear looks like a replacement Mahle piece.
If the original cam gear was the plastic coated toothed al gear, there may be bits of yellowish plastic in the sump or stuck in the oil sump pickup.
Oil filter bypass spring is pretty weak.
If a smaller chunk of gear coating was able to get past the sump pickup screen, it could have gotten past proper filtration and ended up in one of the oil passageways. Being #1 rod bearing is one of the last spots to get proper oiling on the Olds it can be easily starved of oil/pessure as is.
You're gonna want to tear down the engine and verify the oil passages don't have junk stuck in them.

Look into plugging the oil filter bypass on the oil filter adapter, verifying oil pump clearances and possibly a higher pressure spring, and look into oil restrictors feeding the cam to keep oil down on the rotating assembly.

 

My parts finally arrived! A friend was kind enough to put my parts in the car he had shipped over here, this saved a ton . I´ve got a new eagle crank from summit, new sealed power pistons for a 71 Olds 442 with less dish to bring up the compression to around 9.75:1, a new oilpump, bearings, etc. I put in the new cam bearings last night and plastigaged the main bearing clearances. Now everything is coming back apart for final cleaning. The machine shop called, they fixed my #1 rod which had been bruised by the worn and spun rod bearing. Now the fun part begins... edit: Fixed some fat finger mishaps

 

Mike, I haven´t found any plastic parts in the oil pan or pickup screen. I bought a new pump and I´ll see if I can shim the spring for more oil pressure. Thanks for all the good advice. I´ll try and follow as much as possible.