Im having a tough time fitting the coolant hose to the top mounting point on the engine behind the gearbox. (see image attached)  I'm told it will fit, however the tube has a sidewall of .205" and the clearance between the pipe and the back of the gearbox is .158"  as best I can measure. That's .047" SMALLER then the clearance needed BEFORE the thickness of the clamp is added.

Despite this, I have managed to soap up the pipe with dish soap and get it most of the way on, but there is no room for a clamp.  I've tried soaping up the gap between the pipe and the gearbox so that I can rotate the tube, then take a standard hose clamp, open it fully, and Spin the tube with the clamp squeezed between the gearbox and the hose but its just not going.  There is no more room to squeeze anything else in that .158" gap.

Anyone else with the 90 run into this? The only thing I can think to do is loosen up the gearbox bolt, attach the hose, then tighten up the gearbox again and hope for the best.

Any ideas are welcome!

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Did you explain your difficulty with Jan?

Yes, of course, but I didn't have pictures or measurements at that time.

When you say sidewall .205, is this the hose wall thickness?  If so, companies such as HPS Silicone Hoses may have hoses with a little thinner wall thickness that may work. 

Yes, the hose wall thickness is what I was referring too.  Thanks for the tip on the HPS hose.  They state the wall thickness as 5 mm, which is 0.197"  Not a big gain but at this point every little bit will help!

Jan just called and said since it's only 4 PSI, any radiator hose will do and offered to send some other hoses if I wanted.  I'm going to try our local auto parts stores and see what I come up with.  This is the last thing keeping me from starting the engine!

Thanks for your help!

This picture makes it even more evident.  Notice the 3 layers of white thread and how compressed/flat the hose is against the gearbox.

It is nice to use the silicone hoses but no requirement.  They are very thick and kind of overkill for a 5 psi system.  

Try a section of local automotive store hose.  If no luck we can get a section out to you. 

Thanks Jan,

It took a little shopping around to the 3 big auto parts stores around and Advanced Auto Parts sold the same ID hose with an OD of about 1/8" less.  $2.11 a foot.  Its not pretty, but it works.


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