detroit question

[mtadamek]

Just wondering if anyone would know the answer to this question. I have a 1965 41' conv. with twin detroit 8v53's. When I was looking for information on governors my serial numbers came up with those engines having variable speed governers on them. They have limiting speed gov. on them now. Just wondering if anybody knew what they had when they were shipped from Hatteras.

 

[TedZ]

Things that run at variable speeds have variable speed governors. They have a limiting spped to prevent overspeed. Stationary engines like generators have fixed spped governors.

There are better diesel engine folks on this board than me...they will give you more info but i believe what you have came from the factory and very seldom if ever need tweaking.

Ted

 

[Will]

My understanding of the three different types of governors is:
Constant speed = The engine runs at only one speed regardless of load. These are usually used for generators.
Limiting speed = sets only the minimum (idle) and maximum (full throttle) RPMs. In my experience, these are used on boats That's why in a heavy seaway, the engines vary in RPMs depending if the boat is running down a wave or up a wave.
Variable speed = controls idle and maximum RPMs. Additionally, Variable speed governors will maintain any intermediate RPM. For example Idle might be at 500 PRM and Maximum at 1850. But if you set the throttle at 1,000 RPM, the governor would maintain that speed within the power output limitations of the engine. I'm not sure what engine application requires this kind of control.
Will

 

[Nonchalant1]

To answer the question you actually asked (what was on them when shipped) just copy your engine model numbers and serial numbers from your engine ID plates (usually nailed to the ER bulkhead on on the engines) and call detroit diesel. They have the full records of everything on your specific engines when they were shipped from DD. Hatteras just installed them in your boat. DD records are accurate and available to DD people on-line. If you can't find it from the one you call, I'll give you the number of DD here and they can do it.

Doug Shuman

 

[Brian Degulis]

All marine engines should have variable speed governers. This means that the governer controls the engine completly. In other words you tell the governer you want 1800 RPM and the governer positions the rack to acomplish that. If you were cruising at 1800 RPM and put the trans in neutral the governer will reset the rack to hold 1800 RPM without the load on the engine. Of course there will be some fluctuation. Limiting speed means the operator controls the engine and the governer only takes full comand when it's pre set RPM limits are reached. Typicaly trucks have limiting speed governers so the driver has some road feel. In other words he feels the engine slowing down on a grade and pushes the pedal a little harder to compensate. I've seen lots of DDs in comercial boats that have limiting speed governers simply because they were converted from truck engines and the governer was never changed. They work OK but it's harder to dial in an RPM and harder to sync up twin screw boats.

Brian