[Bummo]

Ok, I dont know where to start to explain this. Here goes. So I decide to do a compression check on my 77 BB rc. After running out of time and only getting the 2 front cylinders on each side done I put the plugs back in, wires on correctly, and fire it up. It doesn't start immediately which is a bit strange but I have been probably flooding it during the cranking. As soon as it fires I immediately am hearing a fairly loud tap tap tap, like one cylinder has a rocker really noise all of a sudden. I shut it off, restart, same thing, rev it for 5 seconds, idle, same thing....then I notice the oil pressure guage is at 0 or close to 0. Now, the tapping was like a good sized screwdriver hitting regularly somewhere but I couldn't exactly narrow where in the engine, but it was Immediately on starting, a little too soon for a no oil sound.
So either the oil pump is toast all of a sudden for some reason or maybe I knocked of a wire for the guage?? I can double check the wires and the plug connection to them but this is a bit strange. How hard is it to change the pump with the engine in the truck? I got a used one I could toss in to see if thats the trouble.

 

[william]

I can't offer much advice on your problem, but I can tell you it is easy to change the BB oil pump in the truck. Since it is externally mounted, it is quite simple. One note, if you opt for a high volume unit (like the MP one) you will have to grind your motor mount slightly. There is a hole in the mount to accomodate part of the pump, and the HV ones are slightly bigger, so the hole has to be elongated. Other than that, it is very easy, I did mine in my driveway.
william

 

[Chump]

Could anything have fallen into one of the cylinders while the plugs were out? Maybe you had a piece of carbon break off the combustion chamber and it's now slapping on top the piston? Did one of the plugs break inside the head? Check the wire that goes to the sender on the back of the motor...seems starnge that there is no oil pressure...do you normally see your pressure gauge go right up after start up..mine takes a bit.

 

[macario]

I would pull off a valve cover on the side you hear the tapping on and start her up again. If you see oil gushing up through the oil holes on the rocker shaft then the pump is most likely working and the problem is elsewhere. Seems with a noise like that it is worth the effort to pull the cover and have a look see.

Mac

Ok, I dont know where to start to explain this. Here goes. So I decide to do a compression check on my 77 BB rc. After running out of time and only getting the 2 front cylinders on each side done I put the plugs back in, wires on correctly, and fire it up. It doesn't start immediately which is a bit strange but I have been probably flooding it during the cranking. As soon as it fires I immediately am hearing a fairly loud tap tap tap, like one cylinder has a rocker really noise all of a sudden. I shut it off, restart, same thing, rev it for 5 seconds, idle, same thing....then I notice the oil pressure guage is at 0 or close to 0. Now, the tapping was like a good sized screwdriver hitting regularly somewhere but I couldn't exactly narrow where in the engine, but it was Immediately on starting, a little too soon for a no oil sound.
So either the oil pump is toast all of a sudden for some reason or maybe I knocked of a wire for the guage?? I can double check the wires and the plug connection to them but this is a bit strange. How hard is it to change the pump with the engine in the truck? I got a used one I could toss in to see if thats the trouble.

 

[macario]

Just a hunch, do you have good spark to the plugs you had pulled out? I am thinking that maybe when you pulled the wires you might have broken the connection and one of your plugs is not firing maybe?

 

[Bummo]

Thanks for the replys guys. No, I dont think anything has gotten into the cylinder, and if I cant find a wire loose I will pull a valve cover. I will check the wires etc again but its running OK so I think its firing on all cylinders.

 

[macario]

I'm sure you checked your oil level right?

Let us know how it works out.

Mac

 

[Evildriver-3]

Stop playing with it before you need another motor. take the dist out and pump the pump manually, if you hear a noise like you are describing it is not good, go and get a good mechanical guage