fuel pump block off ?

[mtcamper]

So through tons of research I have found that when blocking off the old mechanical fuel pump you may or may not have an oil pressure loss, if you leave out the pushrod. Anybody here have any real world experiance? I still have the brass guide but no pushrod. This is a long block built to 1800 that I will be running my old 2.0 FI with. I just do not want to be risking any kind of damage or negative affect here as I want this motor to last a long time . As I wrote I do not have the pushrod. So if I do need one can these be purchased anywhere? This issue has really been bugging me as in waking up thinking about it when I wake up lol. I'm willing to do whatever needs to be done just to keep this motor as reliable as can be. Also if I end up putting a pushrod in there; does this cause wear on the cam? Thanks, Ryan in MT

[SlowLane]

Ok, just to be certain: you are talking about a type IV engine, right? With the mechanical fuel pump located on the right side of the engine up near the flywheel?

If so, then yes, removing the pushrod introduces a "hole" in the oil gallery which conveys oil to the valve lifters on the right side of the engine. It may not show up as a noticable pressure drop at the oil pressure sender (which is located at the far end of the oil circuit nearer the oil pump), but it will starve your right-side lifters of oil.

You can bolt on a block-off plate in place of the fuel pump, but the problem there is that the pushrod protrudes out past the mounting surface of the case, so you can't fit a block-off plate while leaving a stock-length pushrod in place.

A couple of solutions:
1) Cut the pushrod so that it fits behind the block-off plate. Make sure you cut it short enough so that it clears the plate even when its at the top of the cam. Be sure to de-burr it so it doesn't drop sharp metal bits into your engine. The rod may knock around a bit, though.
2) Leave the mechanical pump with stock-length pushrod in place. Attach a short length of fuel hose from the inlet to the outlet of the pump.
3) From your posting, I get that you don't have either the pushrod or pump in your possession. In that case, you'll need to source a smooth metal rod the same diameter as the pushrod. Your best bet might be to find a wrecked bus and pull the pushrod and pump from that.

[mtcamper]

Thanks for the tips Slowlane. Looks I'm going to error on the side of finding a rod to put in there if I cannot find an old pushrod. I did talk with the machinest that did the rebuild and he said it is fine without the pushrod. My thoughts are putting a pushrod in is not going to hurt anything, and it may not do anything but at least I will have peace of mind.

[SlowLane]

I did talk with the machinist that did the rebuild and he said it is fine without the pushrod.

Well, it is possible that he tapped in an extra-long gallery plug at that location, which would have the effect of blocking off the oil passage where you want it to be blocked off.

It's unlikely, though. Ask him.

[mtcamper]

Yeah, I really dont think he did that. I just ordered a pushrod from bus depot. I will put it in to be redundant. No harm with it in, unknown harm with it out. For $11 I will take that for the peace of mind. Here is a picture as it currently is.

[Amskeptic]

Yeah, I really dont think he did that. I just ordered a pushrod from bus depot. I will put it in to be redundant. No harm with it in, unknown harm with it out. For $11 I will take that for the peace of mind. Here is a picture as it currently is.

Some engines apparently did not have that bronze sleeve, and no push rod meant no idle oil pressure.
Colin

[mtcamper]

So does this mean it is ok with just the bronze sleave?

[Amskeptic]

So does this mean it is ok with just the bronze sleeve?

Not necessarily. If you see a hole in the sleeve that bisects the gallery, you will have a problem. If you just cannot tell for sure, stick the shortened pushrod in and be done with it.
Colin

[mtcamper]

Thanks for the help that is what I will do .

[vdubyah73]

?'s would the push rod rattle up and down hammering at both the cam and block off? how about a type 1, is the lack of a push rod even an issue?

[Amskeptic]

?'s would the push rod rattle up and down hammering at both the cam and block off? how about a type 1, is the lack of a push rod even an issue?

I have driven a couple of blocked off push rod equipped engines, the pushrod gets pushed to the plate and pretty much stays there.

Type 1, no issue, there is no high pressure gallery intersecting the pushrod bore on a Type 1. IIRC, it is lubricated from camshaft gear splash.
Colin

[vdubyah73]

thnx