Transmission problem

Capt jgw · Feb 17, 2015

It's now called a ZF 50. ZF bought out Hurth many years ago. I don't think the ZF's ate made anymore either but some parts are available. There are several rebuilt units on Ebay.

Calif. Ted · Feb 17, 2015

The Hurth HBW50 has a "checkered" past, I had one in a '94 270 that is still running strong, friends have had theirs fail within a few hundred hours of run time. Rebuilds were also problematic, the replacements were generally one of the ZF models which was only slightly longer. There was a ZF distributor in Miramar Florida, call them direct regarding availability. Couple years ago a friend had this replacement done by a mechanic that specialized in transmissions and I believe it was about $1700.
When they built boats in California, Catalina would buy a bunch of engines at one time from the distributor and use them for several years of production, so the engine sometimes predates the boat.

Capt jgw · Feb 17, 2015

Never heard of ZE. He probably meant ZF. ZF and Hurth are virtually the same, I believe most parts are interchangeable.

peter_ms · Feb 17, 2015

ZF are Hurth

There are a lot of comments on this engine / transmission in past threads and in the C34 archives

I have a POS Hurth HBK-50 in pieces at the moment. The input and output bearing end caps have ZF cast right into them.

2001 C310 Hull #147 with about 625 hrs on it and the forward clutches are toast already. Catalina/Westerbeke are basically responsible for the lack of longevity. The C310 engine platform is too flimsy for this particularly rough engine.

Their joint solution was to up the idle to 1100RPM. A ridiculously high RPM for an engine that maxes out at 3000RPM.
At any rate this causes excessive wear on the clutches.
Another Achilles heel with this engine/transmission is the damper plate. It bolts to the flywheel ant the transmission spline slips into it. It's purpose is to dampen the shock load on the transmission input shaft from each cylinder "explosion". The input shaft is hardened and the damper plate hub is less so, so that it is sacrificial.
So, at 625 hrs my damper plate was significantly worn; maybe 60% toast so if the clutches hadn't failed now; the damper plate would likely have failed around the 1000 hr mark.

So... I am attempting to replace the clutches, I am replacing the damper plate and will be setting a counter for about 900 hrs; when I expect it to fail again since the tranny input shaft does have some minor but not insignificant wear.

Hopefully by then electric conversion will be a more reasonable alternative...

Peter

c130king · Feb 17, 2015

Here is the thread to the posts back when I replaced my Hurth with the ZF-10. Still working well about 18 months and 500 hours later.

http://forums.catalina.sailboatowners.com/showthread.php?t=153186

Hopefully this will provide some additional info. Good luck.

Cheers,
Jim

Clydo · Feb 17, 2015

Rummerful said:
1st of all, let me make it clear that I do not know anything about transmissions. Forward gear would not engage for the 1st 2 or 3 tries. I had it pulled and the mechanic could not find the label with serial # or gear ratio. I called Universal and was told that it is a Hurst (sp) 50-2R with a 2 to 1 ratio. He also said that it is no longer made and does not know if there are parts. I have a 2003 - 310 and the manual for the engine is dated 2001. I tried to read the serial #, but it is on the port side and not much room between the engine and the head bulkhead. I thought I read 2E8507F206. I was told the the E should be a #, but I must have misread some more digits.
Anyone have this issue? Anyone know of a replacement transmission or where to get parts for this one?

Thanks
Eric

Survey on my C310 year 2003 states Hurth Trans model ZF5M with
serial number 38444. Only 293 eng hours indicated when bought
two years ago. Hard to believe PO had to replace? Who knows.

Clyde Thorington
C310 # 245
ILEAN TOO
San Jose, CA

rpwillia · Feb 18, 2015

Damper Plate

peter_ms, et al, There are a couple of threads on this 310 forum about the damper plate issue. Witzend and I both replaced ours on our own, it was not very hard. We even used two different models of damper plates.

Not to hijack the thread a little, but these Universal engines are basically marinized Kubota tractor engines which are the cats meow for tractors. I was helping on a house build once and this guy had one with essentially the same engine we have and that was a very smooth engine. At this point I am out of expertise, but it is curious how rough our engines are.

FWIW I have about 1300 hours on my engine and the transmission has been just fine.

pk104 · Feb 18, 2015

My 2001 has nearly 1700 hours on the transmission and all this talk makes me very nervous also. At least we are on a very small lake.

Tom J · Feb 21, 2015

Over 1400 hours on my engine/transmission, and no major issues. Fingers crossed.

peter_ms · Feb 21, 2015

Rummerful said:
I looked at the ZF6 and for a displacement boat the hp rating is like 18. I have now purchased a ZF10. The mechanic thinks he can install it without modifications. Don't know why some have problems and others (like you) roll along w/o incident. Glad your tanny is working so well. Eric

The ZF10 is an inch longer. If you have anything but the factory 2 blended prop I would be reluctant to add another inch of overhang behind the strut.
Peter

c130king · Feb 21, 2015

I installed a ZF10 but had to remove the plastic shear fitting between the two halves of the shaft/engine coupling to get it to fit. Been working great for about 18 months and 400+ hours.

Did everything while on the water.

Cheers,
Jim

peter_ms · Feb 21, 2015

peter_ms said:
The ZF10 is an inch longer. If you have anything but the factory 2 blended prop I would be reluctant to add another inch of overhang behind the strut. Peter

I hate auto correct and failing eyesight; that is of course 2 bladed, not blended

peter_ms · Mar 9, 2015

OK I have officially surrendered to Hurth...
Got all new clutches and thrust bearings but the originals look great. I was expecting to find them worn or fried.
Then I measured to compare the old and new parts; there is only a .19mm difference. That is less than a folded piece of printer paper.
I am loathe to reassemble it only to find it works (read doesn't work) the same as when I hauled.
I hate to do the basket case trick but that's exactly what I am doing.
Packing up all the pieces and shipping it to the local Westerbeke/Hurth ZF dealer.
Hopefully if he doesn't need the clutches I will get that money refunded...
Wish me luck!
Peter
C310#147
For Petes Sake

KZW · Mar 9, 2015

My survey of 2005 C-310, sail 307, says ZF Hurth Model, ZF 5M, serial number 3302002001. I have no idea what the differences are between the 5E and later models. Only344 hours on the engine.

Long Story · Mar 11, 2015

Rummerful

Check your private messages please...

Long Story

peter_ms · Mar 19, 2015

Well I just got my "rebuilt" HBW-50 back today.
They put in the new clutch and floater plates even though they were the same thickness as the "old" ones.
The report was that "they shimmed the forward clutch back into spec" but didn't elaborate on how far out of spec it was; and why.
Launch is May 2 so I guess I find out then if it is fixed.
New motor mounts; new Sachs spring damper, some new hoses...
2.7 Boat Bucks plus my labour...
Cross your fingers for me on May 2
Peter

swfcruiser · Mar 22, 2015

Hurth Transmission Problem

The Hurth transmission on my Catalina 30 started slipping last summer with less than 200 hours on it. I was informed by the distributor that it failed because of faulty parts and that Westerbeke would replace it with an "upgraded" transmission. The local service providers for Westerbeke removed it on January 12 and have yet to replace it.