Possible Father and Daughter project, 88 Oldsmobile Cutlass Supreme Classic Brougham

Olds 307 and 403

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Oct 4, 2018
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Melville, Saskatchewan
I am particularly happy with my roof bodywork. It is unique and the finish works with the colour. I will get a better pic tomorrow, weird lighting.
20190703_193523.jpg
 
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Olds 307 and 403

Active member
Oct 4, 2018
312
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Melville, Saskatchewan
A little better picture but still looks better in person and full sunlight. I guess the first thing when I come home is take a picture.20190704_200249.jpg
 
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Olds 307 and 403

Active member
Oct 4, 2018
312
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Melville, Saskatchewan
Well the belt setup sounds like it is supercharged. It can't see contact anywhere and the belt has stayed in place. Everything turned nice and smooth individually. Next will be installing the A/C lines and charging it.
 

Olds 307 and 403

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Oct 4, 2018
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Melville, Saskatchewan
I think other than charging the A/C and installing the new cycling switch when it comes, the A/C will be ready to go. The belt is now quieter for some reason, still can't see any contact spots. It got up around 195 on a highway drive and stayed there. I have the fans on constant low speed with key on, the alternator sits at 14.5 volts and idle in park. I retarded the timing a few degrees, it was hitting against the starter. I bumped the idle up to 1000 rpm was around 800 rpm in park. The idle in gear drops to around 500 rpm and is unstable. I need to play with the mixture screws and put a timing marker and my light on it. The acceleration is okay, not sure if the lock up is working. I have had to play with the linkage a few times since changing the selector seal, still barely get park. Maybe I unplugged the the connector, the TCI vacuum switch is right there.
 
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Olds 307 and 403

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Oct 4, 2018
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Melville, Saskatchewan
Well I got the A/C charged. Of course it leaked at the big line on the accumulator, needed double O rings. I also needed double O rings at cycling switch. Of course it wants to shoot at defrost and the floor. I thought I replaced the leaking selector valve, maybe the other one is leaking. I had to tighten up the air gap on the new clutch. Now it engages everytime. The compressor is actually fairly quiet. The gamble seems to have paid off, considering it had sat for 5 years on the shelf.
 

Olds 307 and 403

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Oct 4, 2018
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Melville, Saskatchewan
I found it. It is leaking by the high pressure switch in the back of the compressor. I assume it is held in by a O ring and snap ring? I have two A/C O ring kits, one for the 88 and one for the 94 that I cannibalized half the system for. I can hear a hissing there and oil is seeping out. I will let it bleed down and replace the O ring. It is minor but a PIA to fix. Still need to figure out getting the vents to work.
 

Olds 307 and 403

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Oct 4, 2018
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Melville, Saskatchewan
Well, I got the new A/C switch in the compressor. I must have wired it wrong. Now I have no power at the green wire. I popped the 30 amp fuse, replaced and still no power at the green wire. I still have a very slight leak at the new switch time for JB weld. Can you burn out a controller?
 

Olds 307 and 403

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Oct 4, 2018
312
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Melville, Saskatchewan
Well I put on the new hose for a 70 Cutlass, since that is what the rad came out of. I used a small tail pipe expander and it mostly straightened the nipple. I had to cut 2" off the new Gates lower hose or it kinked, even with the spring inside. Well took the car for a drive there is good and bad. The good, the serpentine belt stayed on and no issues. The transmission is no longer leaking any amount. The coolant leak is fixed. The bad, my cruise didn't work, I should be able to fix it. The car ran around 200+, 210 on the gauge. Assuming the temp gun is right. Plenty hot for a 260, don't think I would consider reinstalling the 350. This cars cooling has always been poor. Also the 15 psi oil pressure with 20w50 oil blows, tired little motor. Also the 18 mpg imperial was dreadful, yes it was over half 10 percent ethanol but 8 mpg less? I even topped up the tire pressure before leaving, if anything overinflated. Also it has taller tires so 150 rpm less. Maybe the headers and 2.5" exhaust killed the mileage? Also I have given up on the A/C as there has to be a bigger leak.
 

JAMCAR223

New member
Apr 20, 2019
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HOUSTON, TX
I like to hear the good. The bad, not so much... Got to get that temp down. If you can get the temp down to a normal 180, you should see a rise in oil pressure, unless it never rises above 15 psi. I would not think that headers, and duals killed the mileage.
 

Olds 307 and 403

Active member
Oct 4, 2018
312
98
28
Melville, Saskatchewan
I like to hear the good. The bad, not so much... Got to get that temp down. If you can get the temp down to a normal 180, you should see a rise in oil pressure, unless it never rises above 15 psi. I would not think that headers, and duals killed the mileage.
I wouldn't think so either. It certainly helped power. The oil pressure starts at 60 cold, then drops rapidly. If I rev it, goes to 20. I will do a compression test on it, this the lowest it has been for oil pressure, it may be dying. It may be the condensor blocking air flow, has a few bent fins. Since this compressor wants to leak no matter what, I will probably abandon the A/C, there has to be a more major leak now, charge leaks out as soon as I put it in. Is there rubber side strips along the radiator for deflectors? Maybe missing air flow directors is this cars problem, has never cooled well, the 403 was a nightmare. I do have a 2300 stall as well for the 2004R. If this car isn't going to get 30 mpg, it may as well run 14's and be fun to drive.
 

JAMCAR223

New member
Apr 20, 2019
27
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HOUSTON, TX
I definitely think a compression test is in order. My car does not have side strips on the radiator, but my Chevy s10 truck does, and my GN does, so GM used them for a reason.
 

Olds 307 and 403

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Oct 4, 2018
312
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Melville, Saskatchewan
Thanks, I will ask on the G body site for pics of those strips. I think the 260's days are numbered.
 

Olds 307 and 403

Active member
Oct 4, 2018
312
98
28
Melville, Saskatchewan

Olds 307 and 403

Active member
Oct 4, 2018
312
98
28
Melville, Saskatchewan
The compression was passable on the 260 for a worn out motor 100 to 110 all 8 cylinders. That compression will never give good performance and obviously a worn out bottom end. I checked the 350 I the 70S, I plan to swap back in, it was 150 to 155 all cylinders except #7 and #8, 110 psi. I added oil, bumped it 20 and 30 psi. So I added the magic formula above. Down the intake till it stalled and fill the down cylinders and let soak over the weekend. Did that twice, #7, now 115 and #8, now 125 psi. Did it again and will let sit till next week.
 
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Olds 307 and 403

Active member
Oct 4, 2018
312
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Melville, Saskatchewan
I fired up the 88 this morning. I wonder if the initial sound was the water pump impeller hitting the front cover. The gasket was destroyed years ago in shipping, it is unique to that reverse rotation pump. I plan on inspecting on removal of the 260 and replacing the water pump anyways, a spare isn't a bad thing. The serpentine belt sounds quiet now, pretty sure the noise is from the passenger side of the motor. Not exactly a knock or clatter exactly. There is a slight exhaust leak on that side. I think it may be wrist pin going. It kind of came and went, now it is more constant. I am thinking wrist pin. Now I plan on upgrading the cooling fan control. I want a direct connection from a toggle switch to override, should I do that from the low fans, thinking so. I plan on getting two, one for into the intake, on a 180, off at 165 and upgrading to a 60 amp relay, since it will fit the current Flexalite contoller. The push in probe didn't work out of box, so I have a 25 amp fuse in between the two terminals, so the low fans come on with the key.
 

Olds 307 and 403

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Oct 4, 2018
312
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Melville, Saskatchewan
I have 12 gauge wires with colour coded heat shrink, 20 amp switch and a 30 amp mini fuse inline for the low fan. The high side is ready to go, just need the bigger relay and thermo switch.
 

Olds 307 and 403

Active member
Oct 4, 2018
312
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28
Melville, Saskatchewan
Took off the belt to eliminate it, the noise is still there, the 260 doesn't sound good. The 350 is a better alternative for sure. This could be part of the reason it is running hot as well.
 

Olds 307 and 403

Active member
Oct 4, 2018
312
98
28
Melville, Saskatchewan
Not much to report other than stealing the .555" boost valve from the core transmission. I plan on just this, 2300 stall which I have and synthetic fluid. I already have the trans just going through a remote cooler. Good thing I don't want a deep pan, PML or Hughes. My last Hughes 2004R pan seeped no matter what. CK doesn't offer the filter extension to run the 700R4 filter with the stock pan or the sheet metal 2004R pan, at least not online. Unfortunately on the Canadian Thanksgiving weekend, mid October, I have to do an oil change, do outer CV boots and put Winter tires on my Daughter's 96 Toyota Tercel so I need to keep my shop open, otherwise I would be spending time pulling this car apart.