FUEL PUMP OUTPUT - just need to verify this with the experts

[racerone]

Re: FUEL PUMP OUTPUT - just need to verify this with the experts

Sorry, you need to look in the right place / places to find the repair kit !!!!------It is available.----These pumps were used on many models for many years.--Run to your friendly BRP dealer and order 393088

 

[Seahorse16]

Re: FUEL PUMP OUTPUT - just need to verify this with the experts

I haven't had time this week to swap coils yet, but I was just looking at them and the are a self-contained unit. The coil and the plug wire harness is a sealed unit. The wire that runs under the flywheel assembly has a quick connect. The only thing I see I could test would be to swap the coil connection to the flywheel. Is this what I need to do?

Racerone: I just searched that part number on ebay and it never lists the correct year for my motor (1976) although the kit looks like the right parts. Thanks. I guess I was reluctant to order the kit since it kept excluding my year. The fuel pump part for 1976 says it's only the same as 1975, but I don't think that is accurate.

 

[racerone]

Re: FUEL PUMP OUTPUT - just need to verify this with the experts

That pump can easily be installed assembled / installed the wrong way.-------Repair kit is 393088

 

[Bosunsmate]

Re: FUEL PUMP OUTPUT - just need to verify this with the experts

I haven't had time this week to swap coils yet, but I was just looking at them and the are a self-contained unit. The coil and the plug wire harness is a sealed unit. The wire that runs under the flywheel assembly has a quick connect. The only thing I see I could test would be to swap the coil connection to the flywheel. Is this what I need to do?

Yes that sounds like it. When you disconnect that it should undo the wire to the coil, nothing else. The only attached wires left on the coil will be the one to ground and the big ht one to the sparkplug. Undo them all and swap the coils over and click back the quick disconnect into the other coils connector. Just make sure that you mark which is the original set up, ie mark which connector coming from the flywheel goes to the top coil and which to the bottom cylinders coil.

 

[Bosunsmate]

Re: FUEL PUMP OUTPUT - just need to verify this with the experts

I put a bit of tape on them with a number 1 for top cylinder , 2 for bottom.
And i mark the top one so that i know the marked one is number 1 too in case the tape comes off.
If it is the coil thats faullty they are about $30.
Sometimes its a sparkplug that has gone bad so you can try swapping them over too since you know one at least gives good spark

 

[mjfrederick]

Re: FUEL PUMP OUTPUT - just need to verify this with the experts

View attachment 225981
Here is a picture of the fuel pump in relation to the cylinders. Hard to tell, looks like in between?
View attachment 225982
According to the shop manual that covers multiple years, doesn't it look like it uses both cylinders?

From what I see in the diagram it looks like the main pumping is done with pulses from the bottom cylinder, but the top cylinder is apparently added in to the mix to give a little bit of help with priming the pump, and probably prevents the pump from becoming vapor locked. Pretty smart design on their part. If just the pressure on the top half is low, the pump would probably still work (just not as well), but if you lose the bottom half you're not going to get anything flowing through there.

Looking forward to seeing what the ultimate culprit is determined to be regarding the no spark issue. That hanging ground wire has me baffled. Looks like it may just be a jumper wire to ground two halves of the engine together?

 

[racerone]

Re: FUEL PUMP OUTPUT - just need to verify this with the experts

There is only one pulse port for this pump !!

 

[Seahorse16]

Re: FUEL PUMP OUTPUT - just need to verify this with the experts

Don't know if I'll get to the coils tonight... My hockey team (winnipeg Jets) is in a must win game in the playoff race.

I saw something about in the manual or a diagram somewhere that talks about a ground wire between the engine block and the engine housing. I need to look again. Does that make sense?

I'm using new plugs so I don't think that should be the issue, but I have spare new ones to test so I will try those just to make sure..

 

[Seahorse16]

Re: FUEL PUMP OUTPUT - just need to verify this with the experts

Oh and I ordered a new diaphragm today too for the fuel pump. Now that I know it's the right part, just want to rule that out entirely as an issue

 

[Bosunsmate]

Re: FUEL PUMP OUTPUT - just need to verify this with the experts

I saw something about in the manual or a diagram somewhere that talks about a ground wire between the engine block and the engine housing. I need to look again. Does that make sense?

It sure does, dont take a loss out on your motor if they lose to the Avalanche

 

[Seahorse16]

Re: FUEL PUMP OUTPUT - just need to verify this with the experts

Big OT win for the JETS! So I double checked the spark on both cylinders. I used to different sets of new plugs, and this time I got a spark in both plugs! I'm thinking I didn't have the plug properly grounded on the upper cylinder the first time. Hmmmm. Now I'm just confusing myself. Maybe all my jostling around regrounded something. Do you think I should still swap the coils or does that sound ok now? Also, should I test the spark jump? I have once of those spark testers that looks like a spark plug with a ground clip, but it doesn't tell you much. Do I need one the "measures" the jump?

 

[Bosunsmate]

Re: FUEL PUMP OUTPUT - just need to verify this with the experts

Dont swap the coils just use your spark tester, set to 7/16 and try that.
If that goes ok post another video of it running
i like ot games

 

[Bosunsmate]

Re: FUEL PUMP OUTPUT - just need to verify this with the experts

If you cant adjust your spark tester just check its sparking on both cylinders and just run it with gravity fed fuel and post a video

 

[Seahorse16]

Re: FUEL PUMP OUTPUT - just need to verify this with the experts

Sorry been swamped lately and haven't had much time work on this. I did get a new compression tester. The just tested both cylinders dry and cold. One read 88 PSI and the other 89 PSI. I've read a lot that you need to warm the engine to get a proper reading, so these may be higher with a warmed up engine, not sure. At least they are similar.

The spark tester i have does not have an adjustment feature, so I may pick up a new one.

 

[Bosunsmate]

Re: FUEL PUMP OUTPUT - just need to verify this with the experts

You can just make one with a piece of wood and two nails 7/16 apart. Hook the lead from the coil to one nail and a heavy lead from other nail to sparkplug. Look for bright blue regular spark

 

[Seahorse16]

Re: FUEL PUMP OUTPUT - just need to verify this with the experts



Ok, so I finally got my fuel pump kit in. I carefully removed the inner diagphram etc from my existing one and started to replace parts. I wasn't confident it was done right, so I found an image online (picture attached) of the steps to rebuild this fuel pump. Here's the problem, my existing one did not contain several of the numbers in the diagram!!! I did recieve these parts in my kit, so I put them in. Was that a mistake?

My current pump did not have #2, it did not have the spring that pushes the button on #3 (but it had the button), it did not contain gasket #5 either.

So I put #2 on, I put the spring under the loose cap in #3, and I put in #5. Did I do this right? Or are these extra gaskets for different pumps? I was just following this diagram. Could that fact that I did not have a spring be the cause of my fuel pump issues? Lastly, there was a tiny spring and a tiny cap that I could not find a home for...ideas?

I haven't ran the motor yet after this change as I have now dropped my lower unit and am attempting to replace seals and impeller. I have some questions on this I will post in another thread.

Thanks,
Trevor

 

[Seahorse16]

Re: FUEL PUMP OUTPUT - just need to verify this with the experts

Ok, FUEL pump finally fixed! Only had to tear it apart and rebuild it 6 times! BUT I'm still having an issue with it running VERY sluggish as you mentioned in a previous post. I am going to test spark jump tomorrow. If this is weak, then does that mean it's an ignition coil more than likely?

 

[Seahorse16]

Re: FUEL PUMP OUTPUT - just need to verify this with the experts

Another thought...would it be prudent to just replace the coils regardless? Not that I want to spend the money, but I'm thinking these are probably original, which means they are 38 years old. Not sure what the life expectancy is on these things....

 

[Bosunsmate]

Re: FUEL PUMP OUTPUT - just need to verify this with the experts

Thats good you can close the fuel pump case off.

Unless you want to spend the money i wouldnt just replace the coils, You could end up replacing a lot if you changed everything thats 38 years old.

It might be the driver coil or something else so id wait til you have done the test first. If you dont get spark on one but on the other dont forget to swap the ht leads and plugs over in case its a dead plug or lead

 

[Bosunsmate]

Re: FUEL PUMP OUTPUT - just need to verify this with the experts

And swap the coils between the different wires coming from under the flywheel too in case a wire from the armature plate has corrupted