Worst Engines of All Time: Oldsmobile Diesel 4.3L V6

[NINETY EIGHT REGENCY]

 

[Drew Dowdell]

Takes 10 minutes out of a 13 minute video of banging on the Olds 350 diesel before he gets to the 4.3 and then he says it wasn't bad.

And that's the TL:DR of it... it wasn't a bad engine like the original 350, but it wasn't a great engine either. They didn't have the failure rates of the 350 because by the time the 4.3 came around they had figured out the main issue of not having a water separator. 

The few cars that remain with the 4.3 tend to just fire right up. 

[trinacriabob]

On 5/31/2022 at 12:55 PM, Drew Dowdell said:

And that's the TL:DR of it... it wasn't a bad engine like the original 350, but it wasn't a great engine either. They didn't have the failure rates of the 350 because by the time the 4.3 came around they had figured out the main issue of not having a water separator. 

The few cars that remain with the 4.3 tend to just fire right up. 

This guy is a character.  He is well spoken and makes some interesting analogies, like "valedictorian of your reform school" at 10:25.  Classic!

I didn't know there was this much overlap.  Sure, we all know about the 5.7 (350) diesel.  At first, Oldsmobile was so proud of it that they badged "cathedrale roulantes" with "Oldsmobile Diesel" instead of just "Oldsmobile" on the rear trunk lids.  My understanding was that the failure rate was about the unchanged block not being able to handle the much higher compression of about 22:1.

But what I learned here and/or didn't remember was that there were TWO 4.3 Olds diesel products.

Since one was a V8 and the other a V6, I'm guessing that the first one - the V8 - was scabbed from the Olds 4.3 (260) gasoline V8 and the 4.3 V6 was a 350 V8 with 2 cylinders lopped off, which is exactly how Chevy got their 4.3 Vortec gas V6 from their 350 V8.

If so, were the cylinder blocks reinforced (differently) by the time they produced these 4.3s?  I can't remember when either of these two engines were released and then retired.  But I do remember that they made it into some Cutlass Cieras.

Interesting that they fire right up.  The funny thing about Olds diesels passing you by is that they sounded like a person gargling.

[Drew Dowdell]

57 minutes ago, trinacriabob said:

My understanding was that the failure rate was about the unchanged block not being able to handle the much higher compression of about 22:1.

It wasn't the block so much as an insufficient number of headbolts which would then stretch under the high compression. Additionally, if there was water in the fuel it would make matters worse because water doesn't compress.

 

59 minutes ago, trinacriabob said:

The funny thing about Olds diesels passing you by is that they sounded like a person gargling.

The only way an Olds diesel passes you is if you're standing still or driving a garbage truck.

[trinacriabob]

12 hours ago, Drew Dowdell said:

It wasn't the block so much as an insufficient number of headbolts which would then stretch under the high compression. Additionally, if there was water in the fuel it would make matters worse because water doesn't compress.

The only way an Olds diesel passes you is if you're standing still or driving a garbage truck.

Realistically, the discussion from the video should be about 2 engines.

I can't believe they went through the trouble of doing a 4.3 V8 diesel.  It was a converted 260 gas V8.  It only showed up for one year, 1979, and in Cutlasses.  One year!  One model!  What a waste of resources.

As for the 4.3 V6, it was derived from the Olds 350 (263 c.i., so 75%) - also, similar stroke numbers as Olds's 350.  I wonder if, since this was a new engine meant to be a diesel, the block and heads were designed with that purpose in mind and maybe that's why it worked out a little better.  If you know, chime in.