Oil pump drive shaft on 283 sbc... too short?

Here´s one for you, I can´t figure it out...

A buddy of mine has rebuilt his 283ci recently.
He had primed the oil pump before he fired it for the first time. The engine started up pretty nice and ran in for about 5-8 minutes @ 1500 to 1900 rpm when he recognized some valvetrain noise showing up.
He shut off the engine immediately and couldn´t figure what happend.

I looked the engine over, pulled the valve covers and the valvetrain looked quite dry. After a bit of searching I found out that the oil pump drive shaft was too short so that the distributor couldn´t turn the oilpump.

Why are there shorter and longer driveshafts? Any idea?
Thanks!
Chris

 

There isn't but one length. Is the pin thru the dist shaft?

shoe

 

For some reason I remember that Chevy2 oil pump drive rods were shorter .I know 283 V-8's used in Chevy2's had different oil pans & oil pumps and I think shorter pump drive rods rods .Check a site like J&W Nova,YearOne,Chevy11 Only..

 

Checked some more &looked up some numbers on the pump rod:
P/N # 3790872 oil pump shaft 64-67 Chevy 11
P/n # 3998287 oil pump shaft 59-73 , all except Chevy 11
My references did not list lengths , so I suspect you have the shorter Chevy 11 drive rod...V-8 Chevy 11's 64-67 did have a unique front sump oil pan (P/N 359940 ) and oil pump assembly( P/N 3793310)

 

The Chevy II pumps are shorter by about the length of the slot in the end of the rod. Just enough for the distributer to not engage the drive rod. Sounds like that might be the problem. It's interesting how many times I've encountered this as there were not that many V8 Chevy II made.

Frank

 

There is also a rod that is LONGER than the common one, I believe for '55-7 with original pump and pan. This is an old and foggy memory surfacing, so find someone with a TRW-FM catalog.

 

Some of the Novas were a little different configuration but I really didn't remember the oil pump drive shafts being one of them. The 65 283 had a long pick-up that went to a front sump pan, but as I recall, the oil pump and drive were the same as all other V-8s. Some of the blocks were different where the clutch linkage mated with the engine, the duece bell housings were a wierd configuration because the fork came out somewhere other then 9 o'clock. Just my thoughts but my memory is old and warn out!

Shoe

 

In a chevy II NUT. The shaft for 283 is SHORTER THAN STOCK. Sorry to the masses who dont have a clue but its shorter. I have built many nova 283's and they were all shorter than a stock replacement.

 

Thanks guys! I´ve already replaced the shaft. It´s about 1/5th of an inch shorter than the regular one.

I pulled the distributor for a couple of times and wondered why it´d drop right back in so easily at the first try...

thanks!

Chris

 

To put a BBC pump into a SBC I had to shorten the shaft. Perhaps the BBC shaft is shorter and that is what you had?

 

15 year old thread, wonder if he ever found the problem?

 

Needed a stroker oil pump drive shaft.

 

he said in last post he replaced

 

see post #9 for the answer to that.

This has got to be a first not only did someone drag up a 15 year old thread but didn't even bother to read it.

 

I was replying to someone who posted about an hour before me that has since been deleted, sorry to offend !!

 

I' m bringing this old thread of mine back from the dead because I found out some more trivia about sbc oilpump driveshafts.
1. Centersump engines like Chevy 2 283s and Opel Diplomat large journal 327s which are pretty common here in Europe will have the shortest oilpump driveshaft at 13.5 cm/ 5.33".
2. Rear sump sbcs will have a driveshaft that is about 1/4" longer than the center sump one @ about 5.96"/ 15.15cm.
3.I have a 1956 283 out of my 56 BelAir , a block without side Motor mount bosses. That block came with a 16.5cm/ 6.5" driveshaft.

I found this out the hard way last night, when I tried to start and run in my fresh rebuilt 327 ex Center sump 327. I used a Melling hv55 oilpump and a stock rear sump pan and the distributor would not engage with the oilpump driveshaft and turn the oilpump. I pulled it out through the distributor hole and put in the only longer one that I had. That was the one from the 56 283. The distributor would engage but not seat against the intake manifold. So maybe this may help some Hambers in the future that are scratching their heads about why the heck their freshly rebuilt engine wont build oil pressure.

 

You must be using a pump drive shaft w/ o the steel pinned collar , otherwise you couldn't pull it up through the main cap ??

 

Yup, I used the factory style with the nylon collar... I guess I was lucky. I used a length of plastic insulated electrical wire, made a loop on one end and went fishing down the distributor hole. When I had the loop around the shaft I used a piece of round tube to hold the loop down. Then I just pulled and the loop tighten itself around the shaft and I could lift it out from down there. Putting the other shaft in I stabbed the pice of tubing back in over the oil pump drive, dropped the shaft in and used a long screwdriver to turn it so it locked in. A little bit of pressure and it clicked into the nylon lock. Worked pretty well and I was sure I didn´t end up tearing the engine down for dropping the shaft in there sideways or something....