Interesting SuperSpeedmaster Predicament

[Sunburnt]

Hi Guy's,

This will probably be a test on your memory but, here it goes, and I apologize for the long explanation (Old Merc's are a new experience for our team and it's all part of the learning curve.).

We are finished on my PowerCat project.. (Twin Merc 700's with Super Speedmasters) I know small motor for that gear case but you've got to admit a cool looking combo,.(yes, I think we have the prop's in the right zone for testing.. 12").. anyways.. The boat is done, and we went for the final check out of the motors since the SSM's and solid motor mounts were installed, the starboard motor wouldn't pump water in a bucket, the port motor spray's the house down. (We've left that motor alone and haven't re-pulled that L/U.) (Both motors run Great!, first pass of the starter and off they go.) but no water out of the starboard motor. We pulled the lower unit and all looks OK, according to the pump base plate and gaskets that were on it (new Impellers). We've pulled and installed the unit several times and could not find anything out of the ordinary. we checked cooling tube length, gasket seal, impeller slipping etc. all OK) but still no water..

Having another SSM in stock we swapped out the waterpump body, base plate and gaskets, (which had the original DR flapper valves and dual feed base plate). Once installed the motor now pumps like a Mother!!. Problem solved!

To get to my point, ( and I apologize for the long explanation) Did Merc ever make a SSM to run on a Left hand rotation Motor?. looking at the base plate and gaskets.(which appear to be factory), that is the only explanation we can come up with... A point to note is that this unit has (to the upper right front of the Cav plate (next to the drain hole) what looks like a factory "C/R" stamped in it.


I'll try to get a good camera and point out the parts in Question.. I know without pictures I'm grabbing at straw's but, it appears this is an odd bird to say the least.. The water pump friction plate and gaskets are not "as shown in the manual" but it takes the Manual "as shown" parts to work..




Jeff..

[Raceman]

First of all, I don't know much about the earlier Speedmasters. I've never been around the ones with single pinions or non-splined prop shafts. That having been said, I'm not sure what the gearcases you're running are.

I've always thought that the term SSM referred ONLY to the later speedmasters which came on the black engines and had 2 pinions (with the exception of the 650X/700X units) If that is in fact what you're running, then to the best of my knowledge Merc never made em to run on a counter rotating powerhead. The thing that I find confusing is the statement: "another SSM in stock we swapped out the waterpump body, base plate and gaskets, (which had the original DR flapper valves and dual feed base plate)." I've never seen a SSM that had DR flapper valves.

I'm assuming that you're turning both powerheads to the right?????

If so it would seem like you'd just need to find the waterpump parts that match the ones on the engine that's pumping water right. Even if the flapper stuff (which again I haven't fooled with in years) fixes the problem it would seem like the age of the rubber there could cause a failure without warning, and since you're probably not going to retrofit temp or pressure guages on early 60's model engines, it might be hard to notice a loss of water, especially on a dual engine boat, until its too late.

I'm really curious about the flappers on Speedmasters though. Sam may already be familiar with it, but it's new territory for me.

[Dave S]

Is a rare SSM thats made to run with a left hand powerhead. That way ya have the strong gears of a right case with a left hand prop for racing left hand corses. The plate under the pump is made with no holes for the duck bills, just one hole- one rotation. Ya going to need a re- setting of the gears under the pump if you want to run it in RH use. What is the other lower unit RH or LH?

[Mark75H]

SSM's were made like this during the very end of the dual engine period ... one motor turned backwards (CCW) and both used the stronger RH type SSM's, like Dave says. The counter rotating motor used a LH prop and had the water pump altered. I'm pretty sure all the pump needs is to have the lower water pump flat stainless steel plate flipped over and the check valve(s) in the correct position.

Dave is right, if the unit was set up for CCW the upper lash needs to be readjusted to agree with the pinion gears if you are going to change the pump and use it as a CW.

I guess this situation comes up once in a while .... and probably ruins a few inline powerheads

[Dave S]

Back years ago. I still have the paper that shows the linkage and gives ya 4 places to have the gears changed. I will try to post the sheet some time. I looks like it was made for 3 carb twisters.;)

[willabee]

What you guys have said sounds right to me.....right handers stamped C/R to run with counter rotating powerheads. I remember flipping the plate, but don't recall what to do about the gear loading. I think this is a McI, but it might help if you want to describe what has to be done.....

[Raceman]

What you guys have said sounds right to me.....right handers stamped C/R to run with counter rotating powerheads. I remember flipping the plate, but don't recall what to do about the gear loading. I think this is a McI, but it might help if you want to describe what has to be done.....

I don't know what that gearcase is, but it's not an MC1. The MC1's had the skeg all the way at the back under the propshaft seal, tapered back exhaust outlet under the cavitation plate, and small propshaft without the taper for a thrust washer. Definately some type of Mercruiser though.

So the reason I bring that up is................... I'm wondering if they did the MC1's that way also, since they came on the original Twisters.

[Mark75H]

I think that is a lefty, too. :)

[Raceman]

I think that is a lefty, too. :)

Definately a lefty. The righties didn't/couldn't use the center/shared propshaft gear.

[Sunburnt]

Is a rare SSM thats made to run with a left hand powerhead. That way ya have the strong gears of a right case with a left hand prop for racing left hand corses. The plate under the pump is made with no holes for the duck bills, just one hole- one rotation. Ya going to need a re- setting of the gears under the pump if you want to run it in RH use. What is the other lower unit RH or LH?


Dave, thank you, the water pump base assembly you describe is exactly what we have so, I guess the mystery is solved and I know now I'm not totally crazy.

A rare piece it appears to be and it throw's a little mud in my immediate plans as both of my Powerheads are CW rotation, but we'll work through it. The Other SSM on the Port motor is a true LH SSM. We do have another RH unit that I guess will be getting a new paint job.

I'll have to look into getting the "C/R" reset..

Thanks again everyone!!

Jeff

[willabee]

I don't know what that gearcase is, but it's not an MC1. Definately some type of Mercruiser though.

So the reason I bring that up is................... I'm wondering if they did the MC1's that way also, since they came on the original Twisters.

I should have checked before I spoke, just wanted to get the cut-away posted before I left for the day. I believe the unit pictured is a McIII.

We wouldn't have countered-rotated the McI in Oshkosh because we only ran them for a short period on singles. However, I seem to recall sending some powerhead counter-rotating kits down to Lake X for the offshore team. If that is true, they may have built a few c/r McI's .....sorry, that's the best answer I can give you.

BTW - I have mentioned on another thread that when we built new powerheads, we used new rods that had the I beams polished and had been magnafluxed. When we rebuilt those powerheads, we magnafluxed the old rods and used them again. It was very rare to find a used rod with a crack and we had started this procedure with the 1250's. I don't remember what all we decided to put in the 1350 Twister I conversion kits, but you have said yours didn't come with rods. That being the case, it must have been decided that based on that experience, new rods weren't necessary and that omitting them would help keep the cost of the kit down.

[T2x]

. However, I seem to recall sending some powerhead counter-rotating kits down to Lake X for the offshore team. If that is true, they may have built a few c/r McI's .....sorry, that's the best answer I can give you.

wn.

Are you talking about these?

[Dave S]

Just put it to the side. If you have anodda RH use that and keep the CR for any powerfull LH work. Why mess with something thats good as is?;)