Hurth HSW 630 V not engaging until about 1,600 RPM when cold

[Jeff d]

Long time, no post. I’ve got my 2000 230 VRS’ transmission acting a little weird this season but only when cold. Not sure what my hours currently are but it’s around 400ish. The transmission doesn’t engage in forward or reverse until about 1,600 RPM when the boat is cold. And it doesn’t really “slip” in at 1,600 rpm, it’s fairly abrupt. I have to make just a minute or two half throttle run and then it’s perfect for the rest of the day. It can sit for a few hours and still be fine but by the next day it’ll be in the same state once totally cooled down. Idling doesn’t seem to do the trick either. I let it idle for 15-20 minutes at the dock the other day and it still behaved like this until I made a higher speed run in gear, then it behaved perfectly fine again.

Fluid level is to the top mark when the dipstick is dipped in without screwing it, per the manual. I’ve had 15w40 in it instead of ATF for 10 years, per the TSB. I’ve lost no top speed or hole shot so I don’t think it’s “slipping.”

My next thought was shift cable. I opted to just disconnect the shift cable, shift the lever at the transmission by hand and then operate the throttle. I get the same behavior with the transmission shifted directly and the shift cable disconnected. Does that eliminate cabling as a suspect?

The oil is a couple of seasons old but looks like brand new Rotella with no water contamination. I’ve never changed the filter (actually didn’t know it had one) so I went ahead and ordered one. It’s pretty likely there’s a 20 year old filter in there. I did get water in the transmission a few years ago when I had a 750 lb ballast bag drain out into the hull while riding, but I checked the oil, found contamination, and replaced it that same day with no noticeable ill effects for probably over 100 hrs since.

It seems/feels like it’s somehow hydraulic pressure related. Any other ideas?

Thanks,

Jeff

[skydyvyr]

I had a similar problem once that was due to a loose fill cap. Is everything tight?

—Sky

[Jeff d]

I had a similar problem once that was due to a loose fill cap. Is everything tight?

—Sky

Like the dipstick or the filter housing? I don’t see how it would matter on this particular design as there’s an open vent with just a dust cap right next to the fill/dipstick hole.

[mikeg205]

Have cooling hoses ever been checked? For some reason pressure not building up to engage. Working at operating temp no problem indicates to me pressure being lossed below operating temp..

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[Jeff d]

Have cooling hoses ever been checked? For some reason pressure not building up to engage. Working at operating temp no problem indicates to me pressure being lossed below operating temp..

Sent from my SM-G955U using Tapatalk

I’ll have to check them but I did get new cooler hoses from the mastercraft dealer within the last 5 years due to the fittings leaking at the crimps around 15 years of age.

[robadele]

I think your idea of manually shifting the trans would eliminate the cable as the culprit. From you description, I doubt it is the cable. Cables don't change much based on hot/cold engine and trans temp.

Unfortunately it sounds like you have a transmission issue that is fluid pressure and fluid temp related. Start by cleaning the 'screen' filter. I would probably change the oil anyway. It is a cheap and easy.

[88 PS190]

I would start by sucking out 1qt of oil and replacing it with SeaFoam Transmission Tune and then give it the old right foot tune up then change the filter and replace the fluid and see what happens.

[sp00ky]

I think your idea of manually shifting the trans would eliminate the cable as the culprit. From you description, I doubt it is the cable. Cables don't change much based on hot/cold engine and trans temp.

Unfortunately it sounds like you have a transmission issue that is fluid pressure and fluid temp related. Start by cleaning the 'screen' filter. I would probably change the oil anyway. It is a cheap and easy.

My Velvet drive on my 94 205 did the same and it required a rebuild as the seals were worn enough to not allow the pressure to build in forward. It got progressively worse and that horrible clunk when it does go into gear at high RPMs...

[Jeff d]

I would start by sucking out 1qt of oil and replacing it with SeaFoam Transmission Tune and then give it the old right foot tune up then change the filter and replace the fluid and see what happens.

I may do that... I think I'll pull and inspect the existing filter first to make sure it's not disintegrating. Am I required to operate the throttle with my right foot?

[88 PS190]

If your hips move like that - color me impressed.