4 HP 1972 Yachtwin - Stalls After 15 min

[DIY1111]

If you look at part 'I' and part 'M' on the assembly instructions - this part I'm referring to is neither of them... Those are the only parts listed and I have this small 'extra disc' that is metal... So, I have (2) small discs - almost the same diameter; one has (4) ears that protrude up ( or down ) and I believe sits between the diaphragm spring and the diaphragm . I'll see if I can attach a pix.

 

[DIY1111]

[No message]

 

[DIY1111]

It’s that shiny disc ?!

And, this is pulled apart as it was assembled - so, parts on the left go on top of part next to it on the right. And so on. Which is different from the assembly directions....

And, this kit 'looks' like its the right one:

https://www.ebay.com/itm/NEW-Sierra...706027?hash=item1a7518c02b:g:67cAAOSw~gZcYeD6

 

[Crosbyman]

I think the 4 legged black one one is a check valve insert ... the 4 legs hold it in place like small hooks

the shiny one is a dome for the main base diaphragm

 

[DIY1111]

OK - with a jewelers loops I found where the (2) round discs go. They have nothing to do with spring support. My fuel pump had no spring support ?!

These (2) discs are supposed to be mounted in the valve housing - they must have come out. There's another set-up just like it in the valve housing. The (4) prongs one hold the silver disc in a cavity in the valve housing. Mystery solved. I pushed them back where it belongs.

The learning curve is steep but manageable !

 

[oldboat1]

oem with instructions (enlarge for a peek). Can check your work: https://www.ebay.com/itm/New-Johnson...YAAOSwX6RcLS3d

On the other hand.......https://www.ebay.com/itm/Fuel-Pump-f...Cclp%3A2334524

 

[DIY1111]

The book with actual instructions ? That would take the fun out of it... besides, what we talk about

As for the referenced replacement - are you sure tgat one will fit my 4hp ? These pumps all look alike.

I’ve always had a thing for OEM parts - and been suspect about aftermarket. But, it is a compelling idea !

 

[Crosbyman]

the china pump fits but needs longer mounting bolts... due to the thicker base


fins one with free shipping....even if it takes a while to arrive ... order two

 

[DIY1111]

Apologies for asking again - but the Chinese pump you sent link to says 6HP and the model #'s do not correspond to the ones I see for the 4hp. Is this the correct one ?

Thx

 

[Crosbyman]

they are basically all the same pump

 

[DIY1111]

Thank you all for the help !

I hope this discussion helps someone else who might need it. You start to think of all the things it can be - and it can get $$$ fast - especially on a motor that has little resale value ( albeit a great 'lil kicker ). Glad I went to the fuel pump first and that I had new replacement on hand.

I put my old pump back together and when doing the two 'blow tests', to assure it was assembled properly, both hose barbs allowed the air to flow - or not, as described. However, both were 'leaking air'. The big barb is supposed to let air flow when you blow in it and it did, but when I sucked on the barb it allowed air to leak.

The smaller barb should not allow air to be blown in, but it did a little, like something was leaking.

When I did these exact tests on the new fuel pump - there was NO air leakage - it was tight. This is the way its supposed to be.

Thanks again ! Until the next time...