Mercruiser 350 fuel pump installation

[skypig]

My mechanical fuel pump went bad on my mercruiser 350 so I ordered one from SKIDIM. It came today and I can not figure out how to get the pump arm under the pushrod. The push rod is fully extended and there is no room to get the pump arm underneath it. Is there a trick to it? Do I have to rotate the engine to retract the arm a bit? Most people complain that the rod falls off and they use grease to stick the arm to it. Thanks in advance. Pat

[True Blue]

Hello, I'm no expert, but I recently replaced my mechanical pump on my '89 Euro Skier, and the rod is rather tough, but I was able to push it up after kind of twisting it barely with my fingers. It was tough, I'll admit. But it was possible. Good luck.

True Blue

[Sunsetter95]

My mechanical fuel pump went bad on my mercruiser 350 so I ordered one from SKIDIM. It came today and I can not figure out how to get the pump arm under the pushrod. The push rod is fully extended and there is no room to get the pump arm underneath it. Is there a trick to it? Do I have to rotate the engine to retract the arm a bit? Most people complain that the rod falls off and they use grease to stick the arm to it. Thanks in advance. Pat

Pat, GM has a nice way to make it easy to hold the rod up. There is a couple of bolts on the front of the engine block directly in front of the fuel pump mounting location. I wish I knew which one it was but I don't recall at this time. You will need to use another bolt with longer threads on it. ONLY FINGER TIGHT for this!!! You do not want to score the push rod. Also, you may need to unbolt your raw water pump or some brackets. I attached a pic of my engine where the bolts are located. In the old days, they use to use these bolts as front engine mount bolts. Good luck.

[scfdfireman]

That's a great tip, but if you also put the engine on TDC (top dead center) by aligning the "0" on the timing plate with the line on the crank it will put the cam lobe for the fuel pump on the flat spot. This will allow the fuel pump push rod to be pushed all the way in and not hit the pump lever when installing.

[skypig]

That makes sense thanks, Pat

[malibucanuck]

I recently replaced mine and while the bolt tip works really well ,I used some thick grease when the engine was cold ,put it on the shaft and pushed it up. The grease holds the shaft long enough to get the pump on. All done after the engine is at TDC.

[skypig]

Unfortunately,the fuel pump pushrod is still in the same spot. When I rotate the engine by hand it does not move an appreciable amount. It moves slightly but not even close to getting the fuel pump arm underneath it. It will turn but it doesn't appear to move and will not lift up. Anyone have any ideas? Pat

[scfdfireman]

It's not a real common problem, but if your sure that it doesn't move when the engine is rotated then the cam lobe is flat. If everything else is fine in the motor get an electric fuel pump from Summitt and a block-off plate for the current mounting spot.

[martinarcher]

I replaced mine a couple years ago and remember have to hold the rod up with my pinkey finger. As I slid my finger out i quickly slid the pump arm in to get it under the push rod. Took a couple trys, but it's in and works great now. Also there is not risk of damaging anything with your finger.

I wouldn't give up on the OEM mechanical pump and go electric since you already have the pump and the boat was designed for the mechanical pump.

[malibucanuck]

If all else fails there should be 2-7/16 bolts holding the cover plate on. You can remove them ,grease up the rod and push it up.You'll need to replace the gasket or if it doesn't tear ,a thin bead of silicone gasket maker to seal it again. In my experience ,if the engine is cold you should have plenty of time to install the pump. Try to only start one bolt, then twist the pump up into place and thread the other, keeping the arm of the pump engaged with the rod. Hope this helps , keep at it you'll be back on the water in no time.

[Sunsetter95]

If you cannot feel the pump rod move up and down (a good 1/2" or so), it is true you may have another issue there with the cam. Probably not. I haven't seen that happen except on a car engine with a lot of miles on it. The bolt is there to use per design. Even with the engine on TDC, you should still have some tension on the pump arm. It won't just bolt up with out touching. I believe I had a gap of about 1/4" at the bolt holes with the top touching.

I you do got electric, you will need to install an oil pressure sensor to shut the pump off in a stall situation or broken line. OEM parts should be used.

Just an FYI. It is possible to install the pump with the arm on top of the rod. I have seen that happen may times long ago... in a land far far away.... wow, I'm getting old.

[skypig]

I wound up getting that pushrod free by dousing it with liquid wrench even up into the hole it comes out of then by rotatating the rod while applying pressure inward. It sounds stupid but I read it ona hot rod website and it worked. I used a bent hacksaw blade to hold the rod in when i put the pump in. Thanks Malibu Crew.

[TheRealMoyer]

Is there any pictorials (exploded diagrams) of the 89 5.7 L Mercruiser engine, especially of the fuel pump and push rod assy.?

[JasonK]

Used to be on MercuryPartsExpress.com. Just punch in your serial number and you can see lots of Mercruiser assemblies.

[Woodski]

@TheRealMoyer - you can also use a parts view from a Chevy 350 small block.  Install will be identical except for marine pump having the vent tube running up to carb and the line from pump to hard is a hardline.

Edited September 3, 2020 by Woodski