Radiator filler base leaking

[Seman]

The radiator filler base on my Yanmar 3YM30 had been replaced by a radiator tech in the US. The epoxy he used was obviously not suitable.
The base have been leaking ever since.
I have tried to seal it with JB Weld Steel, but no success.
Is there anything else I can try?

[tkeithlu]

It should have been brazed. That's a pressurized cooling system. The spring in the cap allows pressurization of the cooling system, so that the coolant does not boil in steady state use. If pressure gets too high the spring compresses and allows steam/coolant to escape through that small hole in the side, sometimes into a small tank.

So, this fix has got to withstand the increased pressure. Gluing it is really not likely to provide that seal, in large part because the glue is being stretched, not compressed. All you've got is the ability of the glue to adhere to the smooth metal.

[Bill O]

I don't own a Yanmar, but a friend did that exact repair on is Yanmar w/good results w/the repair kit. He basically followed the directions given in the kit. Not certain if the directions are online but would give Yanmar a call to ask how they recommend to seal it. I know he did not braze in the replacement neck.

[tkeithlu]

Sounds like Yanmar has had more than one customer with this problem.....

[Wotname]

You guys.... try reading the manual and see how Yanmar wants it done.

OK, I make it easy and post the relevant pages.

Of course if the existing parts have been butchered by others, then some new parts will be required.

[Seman]

Thank you for all the helpful replies.
I have had to order a rebuild kit from Yanmar to repair it properly. The new filler is glued in with Loctite to a copper sleeve.

[Wotname]

Originally Posted by Seman

Thank you for all the helpful replies.
I have had to order a rebuild kit from Yanmar to repair it properly. The new filler is glued in with Loctite to a copper sleeve.

Let us know how it works out and I will be interested to know if the Yanmar rebuild kit includes the two tools or if you have to machine these locally.