blower info

[hwginc]

I am looking for info on blowers for a 6/92 what is this difference on the right and left blower to get them to turn differt directions the gears .shafts or what let me explain,
I recently have rebuilt both diesels and sent the blowers off to get rebuilt along with turbos,etc upon completing the starboard engine she fired and ran perfect, however on completing the port engine no fire and pressure was blowing out the turbo as the engine was turned over I pull the air shutdown cover and discovered that the blower was turning wrong I contacted the builder and he stated it is impossible to build the blower backwards is this true.
Need Karls expert advise
thanks jack

 

[luckydave215]

It's a little hard from reading your post to be sure, but my guess is that you installed a starboard starter in your port engine. I believe they turn opposite directions, so you're crankking the port engine backwards.
And if that's true, have you vacuumed water into the engine?

Or is it only the gearboxes that are different on 92's?
Karl?

 

[SKYCHENEY]

You would know if you had it running backwards. The exhaust comes out of the air cleaners and it runs a little rough. I have done this personally on trucks before. It's not a pretty sight.

I don't think that is the problem here. Did you get your own blowers back after rebuild or were they exchanged?

 

[yachtsmanbill]

I think the opposite rotation blowers are geared with idlers or opposite lobes. I know the fuel pumps and circulating pumps are L & R. Engines with ALLISONs need to spin opposite, but TDs and others can run the gears reversed at 100%.
Gas engines with Warners run LH in and LH out,the 72Cs are not reversable,the 71 series is, while the ALLISONs are drop gears with LH in and RH out and Ls or Rs. Both of my 12-71s with MH20s turn inboard with the gears outboard. With TDs (twin disc) you can run both engines right hand or left.
Eschew Obfuscation !! ws

 

[Boss Lady]

I would start with checking the engine codes and starter codes to make sure they are in agreement. Since you can mount a starter on either side, this becomes important that you have the correct rotation starter for the engine and mounting position. Engine rotation is determined by looking at the front of the engine. Pay attention to this, the starter rotation is determined by looking at the flywheel side of the engine and which side the starter is mounted on. Your engine code will tell you if it is L or R engine rotation. Then look at the starter, LC starter code is for left side mounted Left rotation engine, LD is for right side mounted starter Left rotation engine, RC is for left side mounted starter Right rotation engine, RD is right side mounted Right rotation engine. Confused yet? print this off and take it with you.

Cheers! and good luck

 

[hwginc]

The engines are timed correctly, also have a clockwise and counterclockwise starters facing the front of the engines port crank turns counter starboard clockwise as book calls for.As to the question of the rebuilt it was suppose to be my take in but who knows my question is can the blowers be rebuilt wrong as i ASSUME there is a right and left blower
thanks
jack

 

[Maynard Rupp]

We used those blowers for superchargers on fuel dragsters and I don't remember any ofthem being different. That twisted 3 lobe beater will work the same regardless which way it rotates. We always rotated them the same way but I see no reason they won't work either way. We did change the end plates for beefier ones, removed the locating dowels, lowered the beaters for tighter clearence at the bottom. We then re-drilled and reamed for larger locating dowels and to maintain our closer clearence. We did that to make more boost.

 

[yachtsmanbill]

The engines are timed correctly, also have a clockwise and counterclockwise starters facing the front of the engines port crank turns counter starboard clockwise as book calls for.As to the question of the rebuilt it was suppose to be my take in but who knows my question is can the blowers be rebuilt wrong as i ASSUME there is a right and left blower
thanks
jack

You must have twin disc or other gears and not ALLISONs. Mine are just the opposite. ws

 

[yachtsmanbill]

I would start with checking the engine codes and starter codes to make sure they are in agreement. Since you can mount a starter on either side, this becomes important that you have the correct rotation starter for the engine and mounting position. Engine rotation is determined by looking at the front of the engine. Pay attention to this, the starter rotation is determined by looking at the flywheel side of the engine and which side the starter is mounted on. Your engine code will tell you if it is L or R engine rotation. Then look at the starter, LC starter code is for left side mounted Left rotation engine, LD is for right side mounted starter Left rotation engine, RC is for left side mounted starter Right rotation engine, RD is right side mounted Right rotation engine. Confused yet? print this off and take it with you.

Cheers! and good luck

Ya got me confused Chris. My 12s' starters are both on the same (port) side of the engines. LH and RH starters. Both engines turn inboard and are outboard through the gears Hows Paul doin? ws

 

[yachtsmanbill]

You must have twin disc or other gears and not ALLISONs. Mine are just the opposite. ws

I blew that one !! I always refer to rotation, in my head anyway, from looking down at them from the helm. BOTH turn inboard. A lot of DD stuff is reffered to from the front or the flywheel end. Dont be a dummy like me;think first!!
On steam turbines we referred to the front as the governor end and the back as the generator end. GEs turned clockwise and Westinghouse was counterclockwise. They are always mounted North and South for magnetic center against the earths poles. At least we dont hafta worry about that issue here! ws

 

[hwginc]

Yes I do have Twindisc trans the blowers have two shafts that according to the manual turn to the outside off case to force air these are turning toward center forcing air out of the turbo on the intake side I was hoping Karl would pick up on this thread an confirm if there is a right and left built blower

 

[hwginc]

Ya got me confused Chris. My 12s' starters are both on the same (port) side of the engines. LH and RH starters. Both engines turn inboard and are outboard through the gears Hows Paul doin? ws

Yes both engines turn inboard and both starters are on port side
jack

 

[yachtsmanbill]

Perservere!!

From the Inline 71 Series Service Manual:
"The left-hand helix blower drive gear is driven by the camshaft gear on LA and RA engines and the balance shaft gear on LB and RB engines. The right-hand helix blower drive gear is driven by the camshaft gear on LC and RC engines, and the balance shaft gear on LD and RD engines."
Inline blocks are siamesed for accy mounting clearances and rotation purposes, hence the LA RA LB RB LC RC LD RD designations. but I am not sure about the V series. I would bet that they are too, knowing DD.
My V series books are on the boat, but I would venture a guess that there is a similar arrangement for those as well. You may need to re-open the blower and or accessory gear case to correct this. Make sure you research this before opening up a can of DD worms. Aint that a fine how-do-you-do?? ws

 

[yachtsmanbill]

Now can someone print me a copy of the MH20 allison books? ws

 

[captddis]

I am not Karl, But I will answer. On most V engines the cams and blowers turn the same way. Only the cranks turn opposite. The 6 71 inlines are another story.

 

[SKYCHENEY]

Now can someone print me a copy of the MH20 allison books? ws

Bill
I've got the Allison book on the boat. I'll make you a copy next time I get over there. It may be a few weeks, though.

 

[Maynard Rupp]

I was wrong about my claim of it not mattering which way the blower beaters rotate. They have to rotate so the air travels around the outside, or case side. If they are turning the wrong way, the air will be forced down the center between the beaters. Sorry, my brain drained for a bit.

 

[yachtsmanbill]

Bill
I've got the Allison book on the boat. I'll make you a copy next time I get over there. It may be a few weeks, though.

Thanks Skye! Please let me know what I owe you for postage / printing!
Bill Stephan 630 388 8882

 

[yachtsmanbill]

I was wrong about my claim of it not mattering which way the blower beaters rotate. They have to rotate so the air travels around the outside, or case side. If they are turning the wrong way, the air will be forced down the center between the beaters. Sorry, my brain drained for a bit.

..And I thought I had a BRAIN FART. I missed my bet on the compression direction, but alas, the book shows "outside" of the rotors. ws

 

[yachtsmanbill]

..And I thought I had a BRAIN FART. I missed my bet on the compression direction, but alas, the book shows "outside" of the rotors. ws

So if the engine is cranking correct direction and starts (tries) and blower runs backwards, you are causing absolute vacuum at the blower manifold. Thats a pretty strange twist on things, even by my standards! ws