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I bought recently a fleetwood caddy and discovered with the cadillac forum that my engine was swapped from de 6.0 to the 307 olds. That is why I joined the forum ! I have some questions regarding this engine, looking firtsly to understand what happened in my engine bay !
caddy from that vintage came with olds 307.i believe 1980 was the last year for the 368 then came the pos ht 4100 til i think 1985.at quick glance you need some new belts for starters
I thought all 307 V8's were painted black. Sure it's not an Olds 350? Check the casting number on the area between the water pump and actual block near the intake manifold.
The VIN will tell you exactly what engine the car was born with.
hi,
Thank you all for your answers.
My VIN shows a 368 engine (cadillac I suppose). I know that I have an olds, on the intake manifold, I can read 22503087.
Same indication on the sump’plug. I think it is a 307.
my questions are for the belt and pulleys. I think there is a problem. 2 grooves pulleys dont match with A/C.
thanks.
Last edited by chantecoq; Jun 8, 2020 at 05:10 AM.
Reason: Error regarding ci engine
Your Olds engine should have three groove pulleys, as I think you suspect. I'm guessing that whoever swapped the engine cobbled together parts from the original and whatever donor car they used. Unfortunately, without knowing exactly what was done, it's difficult to know what is correct and what isn't. Olds used three different length water pumps and the brackets and pulleys need to match the pump for everything to align properly. Likely the easiest thing to do is to get a complete set of brackets and pulleys from an Olds 307 as a matched set, or at least provide more detailed photos so we can tell exactly what you have. Those pulleys look like they've been in a lake for a while!
Also, you need to find the BLOCK casting number, as shown in post #5. That will tell us exactly what Olds motor you have. Look above the water pump, next to the oil fill tube and below the thermostat housing.
caddy from that vintage came with olds 307.i believe 1980 was the last year for the 368 then came the pos ht 4100 til i think 1985.at quick glance you need some new belts for starters
Last year for a 368 in a Cadillac is 1981,1982 was first year for 4100.
Thanks a lot Joe.
I have a 5A engine, I think it is a 307.
I guess the previous owner after the swap wanted to keep the A/C with his 2 grooves pulley.. but it is impossible !
My cadillac is in quite bad condition, I would like to make it driveable (as a first step), so instead of changing the pulleys, I thought it could be easier to forget about the A/C (which is probably not functioning).
So I was looking desesperately for belt & pulleys diagrams for 307 engines withiut A/C... this is hard to find.
Reading the forums I understand that with this configuration, the alternator shoud be on the passenger side with a special bracket. Is it right ?
I can see from those photos that whoever installed that motor didn't use the correct spacers on the power steering pump bracket, so that's definitely part of the belt alignment problem.
Unfortunately this photo is small, but the water pump pulley needs to have three grooves. Innermost groove drives the A/C compressor. Middle groove drives the PS pump. Outermost groove drives the alternator.
The early 307's were painted corporate blue. As said, every spacer must be in its proper place. And if you just remove the A/C and only use the one belt on the crank to turn power steering and run the alternator off just the water pump, expect squealing, lack of charging, cooling and the alternator belt actually burning right off. You need either triple groove pulleys or a passenger side non A/C alternator bracket, 5.6" water pump and pulleys. You can space everything out to work around it but it is all trial and error.
Thank you for these advices. I thought it was easier to remove the A/C than to add new three groves pulleys.
Maybe I am wrong !
The thing is that the engine (5A) probably comes from a car that did not have A/C. I do not know where this engine comes from. I guess the transplant has not been done in a correct way. There is a belt that is linked to the crank, the water pump, the alternator and the Steering power. That is amazing. The steering power does not work well because the belt does not really embrace the pulley.
How difficult is it to change the crank pulley ?
I have seen one Olds powered car that was non A/C from that time period. The Vin Y cars used a 2 groove crank pulley even with A/C. Well two real grooves plus the air pump. The Vin 9 cars had thr triple groove pulleys. Removing the A/C on Vin Y's cause major problems.
Now That I am sure I have a 307 olds engine and probably in bad condition (with pulleys problem because I have only two groves instead of three) , I am considering buying a 350 olds and making a swap.
The 350 is a crate engine, with a 557752 3B case, herebelow are the pictures.
The engine is almost new and the price is low.
Does anyone know if the swap is easy ?
In a way, I thought the swap from a 307 to a 350 should be straight forward...even if initially the fleetwood had the original 6 liters.
The swap is super easy. That is a windowed main 350, hopefully it is close to the factory 8.5 to 1 compression. They probably used 24cc dish cast pistons in the remanufacture of that motor.
Well, that definitely makes this motor more desirable, especially if cheap. Everything from the 307 is a direct swap, he should not need any parts unless some of the parts are worn out on the 307.
yes, my current 307 works, so I may have all parts needed, like the rochester, air filter, engine mounts, etc..
The reason why I am not happy with the 307 is that There is a mess for sure with the belts and pulleys. I have two grooves pulleys (for water pump and crankshaft) with A/C, power steering and alternator. Thanks to the forum, I know that it can not work ! I need three grooves pulleys.
Second, I have smoke from outside the head gaskets and the water coolant is boiling.
I may consider buying the 350. And id I need more parts, I ll buy from the US, like rockauto.
Unfortunately the 350 Olds is gone, I was not not quick enough (sold for about $1700) !
So now, I will consider repairing my 307 OLDS (5A).
On of the problem is the belts and pulleys (I have DA, AC and alternator and only two grooves fort crank and waterpump).
I am actively looking for three grooves pulleys (Crank and water pump) ; nothing on Ebay, nothing at Rockauto.
Where on earth can I find these two pulleys with three grooves ?
That would really help me if I could find these pulleys.
i think all you need is the 3 groove water pump pulley,the alternator can run off the outer single pulley,hopefully you can leave the a/c compressor on to keep the laternator belt from doing all the work.pretty sure i have that pulley an d may have a set of 3 groove pulleys
i think all you need is the 3 groove water pump pulley,the alternator can run off the outer single pulley,hopefully you can leave the a/c compressor on to keep the laternator belt from doing all the work.pretty sure i have that pulley an d may have a set of 3 groove pulleys
Hi jcdynamic88,
Many thanks for your reply which gives me hope !
Can you confirm me the belt diagram you think of ?
Is it as shown herebelow?
that is the routing i was thinking of,your alternator doesn't look like it lines up with the p/s pump and it shouldn't for the set up in your last pic.i will check tomorrow for the pulley
that is the routing i was thinking of,your alternator doesn't look like it lines up with the p/s pump and it shouldn't for the set up in your last pic.i will check tomorrow for the pulley
Hi,
Thank you.
Currently, there is one belt for water pump, p/s and alternator, but it is a non sense. The p/s pulley does not really rotate.
Here is the situation (see pic).