Forward is Reverse and Reverse is Forward

KCLOST

Commander
Joined
Jun 22, 2002
Messages
2,095
Re: Forward is Reverse and Reverse is Forward

Sounds to me like he put the wrong lower unit back on, maybe a counter rotating unit with your original prop? :p
 

DHPMARINE

Captain
Joined
Dec 16, 2003
Messages
3,688
Re: Forward is Reverse and Reverse is Forward

Gotta put in my guesses.Wrong gearcase is probably ruled out,as has been wrong prop.I think that means the motor is running counter-clockwise,when looking down at the flywheel.<br />DHP
 

Merc805

Petty Officer 1st Class
Joined
Feb 14, 2004
Messages
202
Re: Forward is Reverse and Reverse is Forward

Now your being silly....<br /> :rolleyes:
 

Clams Canino

Commander
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Jan 10, 2004
Messages
2,179
Re: Forward is Reverse and Reverse is Forward

It's *possible* for that motor to start backwards, but the spark advance would be retarding as he gave it throttle. Not a likely solution.<br /><br />-W
 

DHPMARINE

Captain
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Dec 16, 2003
Messages
3,688
Re: Forward is Reverse and Reverse is Forward

Clams, I'm just thinking back to the 'old' Mercs that only had a pinion gear and 'Forward' gear in the lower unit.Think it had two solenoids,maybe two starters?At rate it did run in both directions for forward and reverse.<br />DHP<br /><br />Golf carts also work this way,but I don't work on them anymore.<br /><br />Don't even want to mention Merc made a snowmobile
 

emckelvy

Commander
Joined
Jan 16, 2004
Messages
2,506
Re: Forward is Reverse and Reverse is Forward

I don't think your 115 could turn into a Dockbuster although it'd be pretty cool !!! lol<br /><br />OK, it was stated that the shift shaft seal was replaced, so he did have it at least somewhat apart. Normally the least intrusive way would be to pull the entire shift shaft bushing assy with the correct tool, and not remove or move about the shift shaft. Of course if he took the shaft out and didn't know the Secret to getting it back in without disassembling the entire lower unit, it may have come all the way apart. That would be a Good Thing to know! Hopefully he's giving you the Straight Skinny on that one. It'd be pretty obvious if the lower unit had been all apart, I guess.<br /><br />I still don't see how it could have full R-N-F if the shift shaft were just installed out of phase. The shift shaft always has to rotate CCW to go to the next gear, i.e. F-N-R.<br /><br />So, here's the possibilities:<br /><br />F-N-R as it should be;<br /><br />N-R-F, however once it jumps the cam past Reverse to get into forward, it should shift extremely hard (if at all) back into Reverse.<br /><br />R-F because once you jump Reverse to get to Forward, you'll never get to Neutral because of the amount of travel the shift shaft takes to get back to the 'detent', when passing Reverse all the way to its normal position (one 'click' away from Neutral).<br /><br />This of course assumes travel in the CCW direction when starting with the control box in FWD gear.<br /><br />Hopefully that all makes sense!!!<br /><br />Unless the guy took the lower unit apart and flipped the shift cam upside down (as was mentioned and is my local Merc Bud Thom Adam's pet theory!), I don't see how it could shift as described. <br /><br />Once the lower unit is down it should be evident what's going on, either something funny at the top end or down below.<br /><br />Keep us posted, this is an interesting one!!!!..ed
 

Clams Canino

Commander
Joined
Jan 10, 2004
Messages
2,179
Re: Forward is Reverse and Reverse is Forward

Originally posted by DHPMARINE:<br /> Clams, I'm just thinking back to the 'old' Mercs that only had a pinion gear and 'Forward' gear in the lower unit.Think it had two solenoids,maybe two starters?At rate it did run in both directions for forward and reverse.<br />DHP<br /><br />
Yes... the 1st inline 6's had 2 starter solenoids and a double pinion on the starter - and ran both ways. That ended in 1961 when Charlie Strang finally convinced Big Carl that he had a beefy enough lower unit to handle the HP.<br /><br />-W
 

andrewkafp

Lieutenant Commander
Joined
Mar 15, 2003
Messages
1,668
Re: Forward is Reverse and Reverse is Forward

Bomber13<br /><br />I am not in the same league as those guys..<br />But I do own a Merc and read a few iboats posts. ;) <br />Some of the members like Clams and Rodbolt are marine repairers or technicians.
 

Dom

Cadet
Joined
Sep 13, 2004
Messages
18
Re: Forward is Reverse and Reverse is Forward

WOW...I didn't know this issue would become famous !!! <br /><br />SO I asked him if he had removed the shift shaft when he replace the seal..He said no. He just replaced the seal without removing it, so he says it is not possible for it to be out 180. Again just to mention and make clear that the boat ran great in F-N-R...No problems, just that is was a little funky getting used to! (being backwards and all) <br /><br />I did notice however that the control lever when shifted to go forward (pulled back in this case) wouldn't give me full wide open because the handle was hitting the cables that come out the rear of control box. In other words, it would not travel to full open position. Everything else ran fine... Just compeltely backwards.<br /><br />Strange huh?
 

Clams Canino

Commander
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Jan 10, 2004
Messages
2,179
Re: Forward is Reverse and Reverse is Forward

Yes... it's now famous. Mostly, because it's almost impossible for it to what it's doing.<br /><br />Lucky you.<br /><br />-W
 

Dom

Cadet
Joined
Sep 13, 2004
Messages
18
Re: Forward is Reverse and Reverse is Forward

I know...and that REALLY worries me. It is almost winter up here in Spokane, and we have one more nice weekend left...Wish me luck.
 

Dom

Cadet
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Sep 13, 2004
Messages
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Re: Forward is Reverse and Reverse is Forward

I know...and that REALLY worries me. It is almost winter up here in Spokane, and we have one more nice weekend left...Wish me luck.
 

Clams Canino

Commander
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Jan 10, 2004
Messages
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Re: Forward is Reverse and Reverse is Forward

It would wory me twice too.<br /><br />-W
 

Dom

Cadet
Joined
Sep 13, 2004
Messages
18
Re: Forward is Reverse and Reverse is Forward

OKAY.....GOOD NEWS..The boat is fixed.<br /><br />Here is the strange part. The mechanic told me that the cam gears in the bottom of the LU were reversed. And they said they were never in that part of the motor, so they still don't know how this could be.<br /><br />So..How in the hell could this have possibly happened? I won't sleep right until I know. Any one?? Any one??
 

Clams Canino

Commander
Joined
Jan 10, 2004
Messages
2,179
Re: Forward is Reverse and Reverse is Forward

Having not had a lower unit apart in nearly a year (other than water-pumps) I'm having a hard time visualazing this.<br /><br />Could he have pulled the shift shaft all the way out and *then* somehow reveresed the cam. All without taking the lower unit apart?<br />We need Ed Mc again. :) <br /><br />Believe me - next time I take a lower apart (and I have a bunch of them backing up to do) I'm gonna be all over this. It just never crossed my mind to look for 'wrong' ways to put stuff together - until now that is.<br /><br />-W
 

Chinewalker

Fleet Admiral
Joined
Aug 19, 2001
Messages
8,902
Re: Forward is Reverse and Reverse is Forward

Hi Dom,<br /> I'm not sure what happened, but there are no "gears" related to the cam i the lower unit. I think the guy made a simple mistake and installed the gearcase with the shift rod about 180-degrees outta synch. That's the ONLY way it could have done what it did. If he had pulled the shift rod out when he re-did the seal, he would have had to pull the entire gearcase apart to put it back in, as the cam is held in place by the end of the shift rod. The spring in the propshaft would have pushed it out of alignment, making it necessary to pull the gearcase apart to realign it. Since the guy said they never had the shift rod out and they never had the gearcase apart, then that leaves having the shift rod 180 off the ONLY possible solution...<br /><br />- Scott
 
Joined
Jun 1, 2005
Messages
4,666
Re: Forward is Reverse and Reverse is Forward

Originally posted by Unicorn.:<br /> Bomber13<br /><br />I am not in the same league as those guys..<br />But I do own a Merc and read a few iboats posts. ;) <br />Some of the members like Clams and Rodbolt are marine repairers or technicians.
Well, this is intersting but I am going ahead with the post to how it is presented. CC you are truly an almanac.
 
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