DonRoc

Also IMCO said expect to rebuild the SC lower ever 50 hours or so. I agree I have a customer with 900+ hp and that's about when we do his. The lower has never broke it just starts making noise and the gears are peeled.. at least it doesn't break, IMCO agreed they said the gears pit and peel, but rarely break in the lower. im gonna give it a try.

JasonSmith

Very good news. Now I just gotta sell my SC uppers.

Mr Gadgets

UD,
is the bearing in the tower that rides on that damaged surface on the shaft, the caged type or the old style, uncaged?

I am also curious if you monitor drive oil temps?

Thanks
Dick

Uncle Dave

I dont know enough about what Im looking at to know-

If I lay out the parts and take picts can you tell me?
Or tell me what to look for?

The bearings seem to be "connected" with another component.

(I have a whole bag of "stuff")

No I dont monitor drive temps, Im usually only going 35-50MPH 99% of the time in the ocean.

UD

Mr Gadgets

UD,
If the parts are in a bag, then look for a bearing that about 1" in dia and 3/8" tall. It will slide on the shaft that has the damage on it. It is located inside of the tower in the case and one inside the tower in the top cap.
A caged bearing has metal between each needle bearing. Uncaged has twice as many needles.. and they rub against each other.
I have seen this galling before, but not often enough to deterime if it is the bearing or a bad shaft. I change the caged ones to the uncaged, but still see it on occasion. Probably a soft shaft (bad part) just like a lot of the other parts they sell these days.

Uncle Dave

Based on what I can tell with a quick glance - it looks caged, but I see both types of bearings.

The shaft doesnt perfectly fit anything with a bearing in my "bag" so Im suspecting a part was left out.

This was installed approximately 12 months ago.

To the drive temp question- the oil on the parts smells like its been REALLY hot.

I do a fair amount of my own work, but I stay away from gears and gearsets.

It doesnt smell "good", but I dont really know what to expect.

Uncle Dave

kap328

Comment:

My comment addresses the statement you made in the highlighted section specifically the part about not losing speed.

I have done more testing on drives with my boat and I can safely say the bold statement above is currently untrue. I have lost a tremendous amount of speed when compared to my SC upper it is not even funny 7-10MPH loss on the top end.

I think the SCX is a good drive but there are issues with it not being discussed in the public domain. I hope to resolve the top end speed loss here real quick it might be something simple or not. I will haul the boat to IMCO here and we will brain storm to see if we can figure out the problem.

The boat runs well on the lower end and the midrange it is only when I put the wood to it i.e...serious HP above 5500RPM that I have problems. No one can figure it out and I am trying to eliminate all the variables.

If anyone has any ideas on how to get my top end back please PM me.

NOTE: I have done the drive comparison directly with a SC drive [swap done the same day] and I can tell you the SCX/SC combination is significantly slower---what is significant 6-10MPH slower and I cannot tolerate such a mph loss.

Therefore, if you have some experience with drives and have some ideas I would love to hear from you now versus chiming in later with an Oh! Yeah! I knew X or Y.

KAP

P.S. Allegedly my bud 26Redline broke his SC lower gear set and no it was not warrantied as of yet. I must say though with only 4 hours on it I would not be happy if that were my drive.

Mr Gadgets

Kap,
with the drive off, does the input shaft turn freely, similar to the SC drive. Or can you feel more drag on it?

My friend put two on his Apache and is running within a couple mph of his XR speed. But his XR's were reg length and now the SCX lower is -2", using 5 blade props.
If you bolt the SC back on, it goes fast, correct?
Seems like it is costing you power on the top. But I can imagine why it is taking that much..
I hope you can find it.. Keep us posted, please.
Sorry I cant be of more help.
Dick

boatcrzy

Not to high jack a thread, but wasnt kap328 running a x drive. I know there was some talk on here about the problems he was having(many). Am I all jacked up or did kap yank the drive and go different direction??

DonRoc

My SCX just came in today.. I have heard of no neglible speed loss over the sc upper. I also have both and will try them side by side when my project is done.