Oil Pump Failure?? (long )

On Tue, 3 Aug 2004 15:13:01 -0500, snipped-for-privacy@webtv.net (Wild Bill) wrote: ]... my guess is the tang on the drive gear of teh pump did not sit far enough into the cam slot. The tang evenetually failed due to this...no longer driving the pump. The tanged shaft is a press fit and can be adjusted...and chould be checked and adjusted during assembly.....thats my guess anyhow...sorry to hear about your misfortune. Oh BTW I would never use one of those junk cast iron jobbies anyhow...but don't think that was teh primary cause.

....Gareth

Sorry to hear about the misfortune, Bill. I assume you were on the way to our VW Meltdown show when this occurred? I heard that your group lost one or two along the way.

Let us know what the autopsy reveals.

Very good guess ..Gareth. I pulled the engine and have not split the case yet. The oil cover on the pump was removed and drive gear pulled. Tang was gone. Not sheared or worn off just gone. Next stop is case split and very close inspection of all the guts.:( Just ordered the Gene Berg 30mm pump. Malcom, Yep that was me that broke on I-65 , just 35 miles from Montgomery! Cruzin Chris '65 Westy dropped his throw out bearing as he pulled into the show area. :( Looks like "Wild" Bill took 1st place in the engine blow contest :) It was a good show and maybe I'll be up for the Birmingham Bug Blast on the 29th of this month. See you there.

"Wild" Bill and "Blondie" Tucker

President and First Lady Rare Air VW Club Pensacola, FLorida

'78 VW Bus ( "Old Rusty" )

'76 Bug "The Grape"

'69 Squareback , Arizona car, Automatic, "Blondies' Car"

'67 Squareback

Rare Air VW Club Website:

...was there anything in the pump cavity that could have caused binding? Do you run a strainer? If th gears bound the tang would shear...otherwise..likely just material failure...did I miention that I hate those junk pumps?? Only shadek pumps used here...

...Gareth

you should not be running a 30mm pump on a street car, stick to 26mm maximum. The engine will run much hotter with the 30mm pump, and you risk blowing out the oil cooler.

John Aircooled.Net Inc.

To Gareath, Have a strainer, no parts /bolts/nuts in the oil pump.

To John, Thanks for the tip. Just curious about the "Running Hotter with a 30mm pump verses a 26mm pump"statement. BTW will also be running the pressure relief cover wth this combo . Thanks again,

"Wild" Bill and "Blondie" Tucker

President and First Lady Rare Air VW Club Pensacola, FLorida

'78 VW Bus ( "Old Rusty" )

'76 Bug "The Grape"

'69 Squareback , Arizona car, Automatic, "Blondies' Car"

'67 Squareback

Rare Air VW Club Website:

I had nothing but problems with the pressure relief combo, the relief sticks open leaving you with 0 oil pressure. After you clean the bypass 3-4 times you'll get sick of it.

Look at the diagram of a VW oil system in your Bentley manual. The oil cooler bypass system is triggerred on oil pressure. If the engine has too much oil pressure, the system assumes that the oil is very COLD and the oil will not be routed to the cooler. If you put a big pump in the pressure may be so high (especially with thick oil) the cooler never gets oil in it, and you can guess what happens to the oil temps. The engine will run cooler with a smaller pump; 30mm is complete overkill for anything but an 8k+ RPM race engine OR a 300+hp turbo car, I'm assuming you have neither of these at this current time.

John Aircooled.Net Inc.

The engine will run cooler with a smaller pump; 30mm is complete overkill for anything but an 8k+ RPM race engine OR a 300+hp turbo car, I'm assuming you have neither of these at this current time. John Aircooled.Net Inc.

Well I don't have a race engine or a Turbo car : ) Thanks for the input John. I'll certainly agree that the larger pump will cause that oil cooler bypass to work as advertised. I'll go with the 26mm and play with the oil relief cover. Any one else had any experiences with cover blockage problems ?

"Wild" Bill and "Blondie" Tucker

President and First Lady Rare Air VW Club Pensacola, FLorida

'78 VW Bus ( "Old Rusty" )

'76 Bug "The Grape"

'69 Squareback , Arizona car, Automatic, "Blondies' Car"

'67 Squareback

Rare Air VW Club Website:

On my wifes Squareback the shaft with the tang actually pulled back out of the gear and out of the slot. Killing her engine. If you notice on a good pump the shaft is inset on the drive gear. Well on my wifes car the end of the shaft was flush with the face of the gear, it moved out of the gear towards the pump cover. Joe

the problems aren't cover blockage, but the relief valves sticking open. It gets real old removing the check ball to remove a burr or small (very small) piece of something that is holding the ball open, which means 0 oil pressure. Proponents of the relief cover will claim that if the oil is clean there should be no debris to stick the check ball open. While this is true in theory, in a real engine the results (my results) were disappointing to say the least. Use a plain cover, you don't need a relief cover if the pump is the proper size in the first place!

I even know guys racing with a 21mm pump, it's good enough if the engine bearings are not worn out.

John Aircooled.Net Inc.

Of course the race guys don't need to deal with a 900 rpm idle speed.

Max

Well as you have read from my very 1st post on this thread I have preformed an autopsy on the dead 1776. Results are as follows. Loose nut from bracket that holds the oil pickup tube. Ended up in timing gear and temporarily wedged itself between gear and block. The resulting shock of the nut and gear banging into the block shattered the tang on the drive gear of the oil pump.:( Will replace Timing gear, distributor drive gear on crankshaft ( which recieved damage from said nut), all the bearings. Will take to machinist shop tonite to have everything checked out and miked as far as wear and tear on the crank shaft, rods, etc. Good news I didn't spin a bearing in the case :). Next I'll work on securing that damned oil pick up tube assembly so that it doesn't vibrate loose again.(Tig weld ?) Expensive little hobby isn't it?

"Wild" Bill and "Blondie" Tucker

President and First Lady Rare Air VW Club Pensacola, FLorida

'78 VW Bus ( "Old Rusty" )

'76 Bug "The Grape"

'69 Squareback , Arizona car, Automatic, "Blondies' Car"

'67 Squareback

Rare Air VW Club Website:

On Tue, 10 Aug 2004 15:29:34 -0500, snipped-for-privacy@webtv.net (Wild Bill) wro

e Next I'll work on securing that damned oil pick

...shop talk forums recently had a thread on the pickup tube...Jake R. said he used loctit 518 I believe...do a search and you should pull thw thread....me....well....I use two part metal epoxoy on the tube where it enters the case to seal and secure it, and loctite 275 (red bearing formula) on the nut....

..Gareth (who wants that damn thing to stay put eternally and never suck air..)

Good to hear you have it all sorted out. Good luck on the rebuild.

-- the Grokdoc Tom Malmevik all that groks is god