Bolens Diablo Rouge and Hus Ski Discussion Forums

Were the seals chabged? Before you tear your motor apart you should determine the "pop off" pressure for the needle. I am still inclined to believe the spring is too strong. The needle should open at about 10 psi

I'm not sure what seals you're referring to?

The only other work I've done on the motor was on the recoil assembly and spark plug cable. I did make a new flange gasket...where the carb attaches to the motor. The motor hasn't run for probably 25+ years. I figured I would start with a refurbished/rebuilt carb and new spark plug to see if that would be enough to get it going again. As you said previously...start with the easy stuff.

For the carb, the snowmobile shop did a complete tear down, clean and rebuild. They said the needle was sticking even after cleaning so they replaced it, along with most gaskets and related components (according to the invoice). I didn't ask if they checked the pop off pressure. I'll check that next. I think I saw a video of that recently so I'll watch it again so I know what I'm doing. I'll have to get a decent pressure gauge first.

Thanks for your patience and your expertise! There are some old timers in my neighborhood that are on my case about getting it running. They seem to be more frustrated with my progress (or lack of) than I am.

Here are some pics for reference...

3 more pics...

It is difficult to determine from photos....but are your piston walls scored?

Im referring to the crankcase seals.

I looked closer at the piston, looks like there is some scoring there.

I have been following your thread and I noticed something since you posted those pictures that I really didn't catch in your opening comments. You said you had an HR carburetor. I am unaware of 444's and Hus-skis in general using an HR carburetor. Normally they use an HL carburetor but after seeing your pictures and seeing the HR carburetor, several things come to mind. Some HR carburetors like the one used on the Diablo Rouge use an external pulse line to operate the fuel pump and I just can't quite see from your pictures if your carburetor has that external pulse line. If it does have an external pulse line it will look like a fuel line connection. However if it does have an internal pulse line like the HL carburetor has, the pulse hole on the carburetor must line up with your manifold block (or carburetor spacer) and yours looks quite different from a standard Hus-ski HL block. The holes in the manifold block must line up with the hole on the cylinder head for the pulse line and with the base of the carburetor. At any point if those holes don't line up (being a different carburetor mounting plate) you effectively block the pulse line which means the fuel pump will not operate. Also in your picture I noticed that when you removed the carburetor, you removed the manifold block with the carburetor so definitely check the gasket between that block and the carburetor to make sure that that gasket is allowing all the holes to line up. Hopefully this will all make sense and help solve your mystery. I think this is the first time I have seen an HR carburetor on a JLO 252.. hmm interesting...
I do agree with Barrie - your piston looks to be quite scored. This could possibly be because you have just a screen on the carburetor allowing lots of dirt to go right down that carburetor. Again HL uses a cover over the carburetor opening to prevent debris from entering the carburetor.

I noticed there wasn't much information related to HR carburetors on the forum. Makes sense now. My Dad got this 444 back in the mid to late 70s. The HR was the carburetor that was installed when he got it. He used the machine quite a bit back then so I know it works...just not sure why it stopped working.

This HR carburetor is stamped as HR2A. It does not have the external pulse line. The pulse line holes do line up from the cylinder head through the spacer block and carb. I hadn't disconnected the manifold block from the carburetor previously. I just did that tonight. The gasket is definitely in bad shape so I'll make a new one. That might be part of my problem.

Regarding the piston, I definitely see the score lines but when I run my finger across it I don't feel them. Not sure if that means anything.

I've attached some additional pics of the carburetor.

A few more pics...

I have a Tillotson document dated May, 1968 the states the HR2A was made for the JLO 252 in 1697 along with the JLO 292 and 297..