Jump to content

3 New questions


Recommended Posts

Hi guys, I hope you’ve all had a happy Christmas with your families! 

I have 3 new questions. Hopefully they straight forward. I have checked older posts and it has briefly touched on the subjects:-

1. We have a perfect rubber fuel tank, with a fuel stabiliser will it hold up to the modern petrol. A previous thread said no to modern fuel, it goes to jelly but no mention of a stabiliser. 
Is anyone running the rubber tank with success?   

2. our internal fuel pump in the tank is in a bad way but fixable! (full of crust, some rust and crystals) I can take the time to rebuild it with new motor brushes, cut new gaskets, solder the electric cable back and clean it all to a usable standard. Are they reliable when good and can they withstand our modern fuels? 
Is any one running the old internal fuel pump? Am I better off hiding a modern pump inside the fuel tank for reliability?

3.  I have put a new thermostat in our engine. Unfortunately the original one had leaked it’s fluids and did not work. I have used a modern 180F thermostat. Should I have gone for the lower temperature 160F so it opens quicker? The engine will hit a peak temperature and the thermostat will stay open anyway. I appreciate your thoughts? 

Thanks in advance 











Link to comment
Share on other sites

Hi Byron,

Can't answer your fuel tank and fuel pump questions as I have the mechanical fuel pump and a metal fuel tank however I can offer my thoughts on the third. I have taken the advice from my engine builder and retained the 180 thermostat. My weasel will not do a lot of lengthy running and the advice I received was thats its better for the engine to run at 180 in order to help burn off the contaminants in the engine oil (that accumulate from short runs) and also helps to reduce wear on the engine components. Thats the theory anyway so I will see how it goes when put into practiuce.

Link to comment
Share on other sites

Byron - I am a newbie on most of these Weasel mechanicals too so not much to offer with respect to the fuel tank/pump. 

As for the thermostat, I don't believe it will matter.  From initial testing onward, it appears that these machines run on the hot side (in warm climates) which is not surprising given the radiator location, indirect air flows and lack of outlet for heated air once it passes thru the radiator.  Presumably, all of these factors were a non-issue given that Weasels were designed to operate in extremely cold conditions.  I would guess that keeping the motor warm enough was a bigger issue than too cold - thus the radiator/cowl doors. 

These thermostats begin to open before their rated temperature and are designed to be fully open at the rated 180 in your case.  That is a desirable operating temperature range - hot enough to be burning off any condensation but way short of any temperature one should start worrying about oil degradation or other heat related wear issues.

Regards, Patrick


Link to comment
Share on other sites

Ok, that’s brilliant information on the thermostat guys. I really appreciate that! 
I will now be keeping the 180 Thermostat in the weasel.

can anyone answer my other two questions regarding fuel pump and fuel tank who are running Weasels?? 

Link to comment
Share on other sites

I have two weasels both with rubber tanks. Both pumps are not working. I have looked at them and they are not in bad shape so one of these days I will look into repairing them. Both weasels have electric fuel pumps that are non original and have worked just fine but when the day comes to restore them. I will definitely repair the in tank pumps. As to your question I have never repaired one. I did buy the fuel pump manual from Pat which looks very good as far as information on repairing these pumps. Sorry Byron were all learning from you.


Link to comment
Share on other sites

Still in great shape never worried about the fuel. Never used stabilizer either. This does not mean you shouldn't just that I never did. I recently cleaned the inside of the tank on my most used weasel and the tank was really in great condition inside. F rom what I heard about ethanol in these tanks I was prepared for the worst.



Edited by M29
Link to comment
Share on other sites

My experience with the fuel pumps is that the die-cast material is the weak point. Many parts are screwed to the die cast and the threads tend to rot away. Especially had trouble with the brush retaining screws coming out. I finally went with 1970s Cadillac fuel pump inside the original case and brackets. Works perfectly, and sounds exactly the same.

Edited by Jesse Browning
  • Like 1
Link to comment
Share on other sites

Thank you Jesse, I managed to get mine apart so with a good clean and a very light cabinet blast clean on certain areas I could get her working again. But I didn’t want to waste the effort if it wouldn’t last for long with the modern fuel.


Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Create New...