Throttle Speed Adjustment

[KWKloeber]

Looks like all is well.

Isn't it GREAT when you discover that things turn out to be, whew!, that simple. 

Troubleshoot, troubleshoot, troubleshoot - before replacing, adjusting, and tinkering
That's my story and I'm stickintoit.

[Ron Hill]

Tim : Just like I told you, I am not surprised!!   

A thought   

[Stu Jackson]

Good to hear, Tim.  And thanks so much for checking and taking the time to let us all know.  Not only do you know and can set aside your concerns, but we have all learned something.  And Catalina got it right yet again. 

[Dark n Stormy]

I like a good tool as much as the next guy but I have a cheap easy way to verify any RPM with a strobe.

I found a free app (Iphone) used to verify RPM on a record player.  Adjusting the RPM on the application to match a paint/chalk mark on the crank pulley to confirm rpm.  Or setting the engine RPM and matching the App to that RPM to confirm accuracy.  Confirm all to the tachometer. 

You could see about turns of the driveshaft or rotation speed of the alternator etc.  I deleted the app but it was good for confirming that my tac was in sync with actual RPMs.

On this post topic.  My bottom and assume prop were so dirty that I was only able to get to about 2600 RPM at full throttle a few years ago.  definitely dragging the works down. 

Brent   

[Paulus]

Ken, Your adolescent comments are totally inappropriate.  I think you owe Stu an apology.
If you can't say something positive, don't say anything at all.
Paul

[BJeansson]

Hi, have followed this carefully as the set screws on my M35 have both a wire and plomb-seal. Max rpm I can reach with WOT is tops 2100. Cruising speed is depending on conditions anywhere 5-6.1 knots with a temp of around 185-190.
Seems to be this setting has been in place for ever!
Should I change the screws to get higher rpm and possibly speed?
Motored from Annapolis to Rock Hall last Tuesday (before IDA storm came around) in flat 3 hours mooring ball to dock.
Thank you for advise.

[KWKloeber]

[edit: PS, 185-190 is too hot to run in salt or brackish water.  You might also troubleshoot why -- and verify that your TStat is opening and is the correct one (160F) for salt and not (180F) for fresh water.]

Bo

I think the same answers/replies as below re: Tim's problem probably also pertain to your 35.

The key is to first confirm that the tach is reading correctly (you are actually running 2100.)  As I said previously:

.....did CTY adjust the engine after installing the cable? 
Or if something is amiss, might it have shipped from Oshkosh that way? 
Or did a PO adjust something? 
Or is the tach off? 
Or, is the governor getting messed up. 
Or..... (insert another cause.)

[waughoo]

[edit: PS, 185-190 is too hot to run in salt or brackish water.  You might also troubleshoot why -- and verify that your TStat is opening and is the correct one (160F) for salt and not (180F) for fresh water.]

Can you elaborate why there should be a difference in Tstat temp for salt and fresh water?  I cant sort out why they should be different.

[mdidomenico]

Can you elaborate why there should be a difference in Tstat temp for salt and fresh water?  I cant sort out why they should be different.

i'm no expert, but i believe the salinity of the water changes it's boiling point.

[Jim Hardesty]

Max rpm I can reach with WOT is tops 2100. Cruising speed is depending on conditions anywhere 5-6.1 knots with a temp of around 185-190.

First thing that comes to mind is over-pitched prop.  Do you know the pitch?  Try, transmission in neutral full throttle, a few seconds or a little more, what is your RPM's.  That checks your governor, if it's not to spec check the tack with hand-held laser tack.  Sounds to me that there's a number of issues that may or may not share a common cause. 
The first thing I would address is the temp, then check/verify the max RPM.  The very last thing I would do is break that governor seal.
Jim

[KWKloeber]

[edit: PS, 185-190 is too hot to run in salt or brackish water.  You might also troubleshoot why -- and verify that your TStat is opening and is the correct one (160F) for salt and not (180F) for fresh water.]

Can you elaborate why there should be a difference in Tstat temp for salt and fresh water?  I cant sort out why they should be different.

Sure but wow - This thermostat issue has been discussed umpteen times herein and is in the Westerbeke engine Service Bulletins and on the TechWiki.

"Our" Kubota engines that went into landlubber tractors and other industrial end-user equipment ran 82C (180F) thermostats. Diesels are more efficient/run better at higher temp but in salt water higher temp causes a precipitation of salt compounds in the cooling path.    Temperature is ESPECIALLY important in seawater-cooled blocks such as the original Atomic-4s, early small Universal diesels, etc., because the deposits end up in the internal cooling paths/ports and can ruin a day of sailing.

So somewhere early on Universal Oshkosh figured out to not use the 82C OEM Kubota TStat (probably spec'd Kb to supply a 72C one or sourced it in the US (as an aside, note that our TStat caps are different than equipment with radiators, and could have been mfgr'd here or supplied by Kubota.)

There's several mentions on here about the seawater-injection wye above the muffler getting caked with deposits and partially/totally blocking the flow. Check the Service Bulletins (Wiki Manuals page) - 160F is the Westerbeke-supplied TStat (also available from Kubota and aftermarket.)  In fresh water of course there isn't that problem so the higher TStat (180F, Kubota and aftermarket) can be used.  (IMO **should** be used.)

This is a water-cooled riser (not the Westerbeke brand) that had been 100% blocked with deposits - note that in this scenario salt water is hitting the hottest area, right at the engine exhaust discharge before the two mix. That's somewhat analogous to the injection wye location.

(PS: I can't cite the original source, but the pic (and similar) are on various member forums/sailing sites/Moyer A-4 forum.)

[waughoo]

Thanks... I would totally understand if it were a raw water cooled block, but hadn't figured out how it made sense in a fresh water cooled system.  Thanks for the detailed explanation.

[Ron Hill]

All : Oshkosh did run the engines after they were built.  I believe what you are asking - did they set the governor stop during that run? .... Don't think so???

I'm most certain that on the production line floor "Paco" was told to attach the throttle cable from Edson to a measurement of (?) and then tighten the set screw.  It would seem to me that it should have been the dealer that checked the engine settings during commissioning!!  Don't know "who" put on the lacing wire with the lead seal on the throttle stops???
Just don't think that I'd build a engine and on its first run rev it up to max rpm!! 

FYI, On aircraft engines you do not do that.  That's why the first takoff is so hairy!!! - that engine is only run at reduced (cruise) power for the 1st hour running!!

A few thoughts

[BJeansson]

Thank you for the feedback.
Prop is a 3 blade Michigan Sailer 8/89 15RH12.
I think I read somewhere that the cruising temp for the M35 was 185-190...
The rpm gauge is working but the hours have not moved since we bought the boat (11/2020). 1045 hours on the numbers, who knows could have been 1045 for the last teen years.

[KWKloeber]

Thank you for the feedback.
Prop is a 3 blade Michigan Sailer 8/89 15RH12.
I think I read somewhere that the cruising temp for the M35 was 185-190...
The rpm gauge is working but the hours have not moved since we bought the boat (11/2020). 1045 hours on the numbers, who knows could have been 1045 for the last teen years.

The listed ops temp is 165-195 - that's from a Wb reprint of the original Univ Oshkosh manual/data so I suspect it may embrace salt and fresh water use. Naturally seawater temp affects it.

As a ref point I normally run 160 with my 3 cyl (unless I get an air lock) so I would expect a 4 cyl to bring that up a bit but not 30 degrees.
I'd check the flow path for salt deposits - if there are, reduce. If none then run hotter but check it on a schedule.