R3 Problem!

[mfg]

What mechanical  malady did Studebaker Avanti R3-4 engines have in common with the '55-'56 Packard V8 engine?

[Dwight FitzSimons]

Lubrication problems?

[Nelson]

Wrist pin?

[brad]

yes, the wrist pin is shrunk in the rod and sometimes works loose.

[Dwight FitzSimons]

And, the solution for this is "buttons" on the ends of the wrist pins?

--Dwight

[mfg]

15 hours ago, Nelson said:

Wrist pin?

 

11 hours ago, brad said:

yes, the wrist pin is shrunk in the rod and sometimes works loose.

Interesting thought concerning loosening wrist pins..This will happen on the Packard with high miles, however, never heard it was a potential problem on the rare R3.

[mfg]

16 hours ago, Dwight FitzSimons said:

Lubrication problems?

Yes, that was my thought.....The Packatd is known for engine oil pump issues..and the R3&R4 oil pump supposedly has a design flaw concerning its fixed pin/bottom plate weakness.

[Nelson]

I didn’t know they had an oil pump problem. I know Lionel Stone tried making R3 pumps out of standard pumps by boring the gear pockets deeper and using six cylinder pump gears. Dwight, didn't you have a failure on one of your R3’s using this setup?

[Dwight FitzSimons]

10 hours ago, Nelson said:

I didn’t know they had an oil pump problem. I know Lionel Stone tried making R3 pumps out of standard pumps by boring the gear pockets deeper and using six cylinder pump gears. Dwight, didn't you have a failure on one of your R3’s using this setup?

Yes, exactly; My R3's second oil pump failed because Lionel Stone's machinist machined the gear pockets of a standard housing deeper for the R3's longer gears.  That made the iron housing too thin and it broke.

 If I had known then what I know now I would have given the engine builder the NOS standard oil pump to install that I already had (& still have).

[Nelson]

WhenStudebaker received the shipment of R3 rods they failed inspection for the wrist pin diameter was at the high limit. The rods got approved with a deviation permit. I know of several failures due to the wrist pin broaching the cylinders. With possibly  50 of 110 or so engines using the R3 rod, several is a pretty high failure rate.

[Dwight FitzSimons]

1 hour ago, Nelson said:

When Studebaker received the shipment of R3 rods they failed inspection for the wrist pin diameter was at the high limit. The rods got approved with a deviation permit. I know of several failures due to the wrist pin broaching the cylinders. With possibly  50 of 110 or so engines using the R3 rod, several is a pretty high failure rate.

No doubt that is why Dave Thibeault put "buttons" on either end of the wrist pins on my R3.

--Dwight

[Nelson]

Dave had a failure on an R4. He was able to sleeve the cylinder and save the engine.

[brad]

We use spiral locks to retain the pins in the pistons. It's less weight. 

[mfg]

This is interesting, little known stuff!!