thunderbolt 500 please help with gear adjustments

Hi,

If I shift the shift shaft, it goes in all gears if I rotate the shaft counter clockwise looking at it from the top, is this the right rotation? The manuals I have are sometimes pretty vague and it's easy to get mislead.

Any help would be appreciated

Re: thunderbolt 500 please help with gear adjustments

The rotation in service is CCW from Forward through Neutral to Reverse, then CW from Reverse through Neutral to Forward.

Using finger pressure only

Forward: Prop will turn (ratchet) CW but not CCW
Neutral: Prop will turn freely in either direction
Reverse: Prop will not turn in either direction except for gear mesh.

Gerry

Re: thunderbolt 500 please help with gear adjustments

Thanks for the info. Gerry,

There's only one thing I don't quite understand, When you say using finger pressure only, do you mean the shifting is finger pressure only or the turning of the prop?

Thanks again

Don

Re: thunderbolt 500 please help with gear adjustments

Don;

My apologies, I meant finger pressure for turning the prop.

Gerry

Re: thunderbolt 500 please help with gear adjustments

Thanks for the info. Gerry, it's very appreciated!

Another problem I have is trying to make the gears work with the remote cables. I put the lower unit in forward, set the remote in forward, join the engine to the lower unit, but I can't seem to get the neutral and reverse working. The neutral worked for a bit, but when we tried adjusting the cable for it to go in reverse the only gear I have is the forward, no more neutral.

How touchy should the shifting be? And is there anything I'm doing wrong?

Also, the shifting cable only extends a little forward, but when put into reverse or neutral it moves quite a bit more, is this normal?

Thanks for any info. on this,

Don

Re: thunderbolt 500 please help with gear adjustments

Don;

If this is the 1968 Merc 500 you were talking about in your previous posts, do you have the s/n for it?

With both units in FWD, it sounds like you do not have the reverse cam set correctly. When the gear selection is Neutral or Reverse the cam pushes up a rod, securing the locking pawls to prevent the engine from rising.

1968 parts list:

http://www.crowleymarine.com/mercury-outboard/437.cfm

See item 46 under GEAR HOUSING ASSEMBLY, COMPLETE (PAGE 1). If you scroll down to 46 and double click on the picture it will blow up for you. This is the cam that must be set correctly on the LU shift shaft prior to inserting the LU into the leg.

Item 13 under CLAMP AND SWIVEL BRACKET ASSEMBLY the locking pawl that prevents the engine from rising in Neutral and Reverse.

Item 7 under DRIVE SHAFT HOUSING ASSEMBLY is the rod that is connected between the shift cam and the locking pawls.

When you blow up the picture of the cam, you will see the ramp surface on it and in Neutral and reverse the end of the rod is sitting on the top flat portion of the cam. In Forward, the rod slides down the ramp, thus unlocking the pawls and allowing the engine to rise if you hit something in the water.

Here is a link to the condensed version of the Clymer Service Manual which you should download soonest as the link is short lived.

http://web.ebscohost.com/serrc/pdf?...97a5-19c00459a11d@sessionmgr114&vid=4&hid=123

You will see the pictures with reference to the cam position on page 128. Depending on the s/n there were two types of cam used, one being a two piece metal cam, while the other is a composite one. Figure M9-48 is the newer type of composite cam.

Read all of this and if you have a problem, let us know, hope it helps.

Gerry

Re: thunderbolt 500 please help with gear adjustments

Gerry is running the answer, but a little comment. Remove your remote control at the engine and see if you can move the shifter linkage in the engine, where the remote cable connects through the gears. Remember don't force reverse; rotate prop as you are trying to put the shifter in R with the engine not running..dog and cams have to line up in R.

Get back.

Mark

Re: thunderbolt 500 please help with gear adjustments

Hi Gerry,

Thanks for the info. it's appreciated!!

I've followed the instructions you gave me, but it didn't work out, I changed the cam shift around, (in the lower unit, the one you have to strip everything down to get at. No, to shift gears I need to go clockwise for the shifting going from forward, to neutral to reverse and it made more sense since the other way around the two part cam (where the l/u joins the motor) wouldn't be able to travel on the ramp.

I know you said that the gear shifting should be the other way around, but the two part cam just wouldn't be able to travel the ramp. Does this make any sense?

I also noticed that the cable of the controls doesn't travel very much when I'm pushing it forward. But when activated in reverse the traveling seems to work good. Now, here's a stupid question, I read on another thread that the first cable to move forward is the one that goes to the gear box. But since either one of the cables move forward when activated, what could be the problem? Is there an adjustment in the control box that needs to be done?

Gerry, I've tried to make it travel freely with no cables attached and it seems to bind when I push it towards the cable side.

The serial # for the outboard is 2247928

I know it's a big post, sorry...

Re: thunderbolt 500 please help with gear adjustments

Don;

Having a hard time understanding. The only cam I am talking about is the visible cam which sits on top of the splines of the lower shift rod. I think, if I can understand your post, that you removed the carrier assembly to work on item 56 in this link:

http://www.crowleymarine.com/mercury-outboard/parts/437_20.cfm

Is that correct or not?


The s/n comes up as:

50 500 4-cyl 2097445 2305100 1967 USA

From here:

http://www.marinshopen.se/Motorer/O...Mercury2takt4cyl4085hp/tabid/487/Default.aspx

As you haven't been here for a few days, I doubt if you were able to download the service manual, so here is the link again:

http://web.ebscohost.com/serrc/pdf?...b18a-af0874f8099c@sessionmgr113&vid=4&hid=105

As a 1967, this would be a more accurate parts listing:

http://www.crowleymarine.com/mercury-outboard/395.cfm

Gerry

Re: thunderbolt 500 please help with gear adjustments

Ref your control box, which one are you using? Is it the older box with a shifter and a warmup lever which lays flat on top of the box? If, so and you disconnect both cables at the engine and lay them somewhere that you can watch the ends and see which one moves first when you advance the shifter from Neutral to Forward. This will be the shifter cable and fits the bottom sliding rail in the engine. Then the throttle cable is mounted above it.

Gerry

Re: thunderbolt 500 please help with gear adjustments

Hi Gerry,

I've downloaded the manual, I've tried everything I read. I was about to call it a day when I noticed a screw right where the shaft from the engine joins the shift shaft. And it appears that the shift shaft from the engine doesn't engage properly when I try to shift, as a matter of fact, the shaft lifts up from the engine cowl and if we tap it back in, it goes in no problem.

The lower unit can be shifted from forward, neutral and reverse no problem when engaged from the lower unit shift shaft, the track the shift linkage travels also moves very easily when no cables are connected up in the cowl.



the shaft I'm referring to that goes up when shifting is #55 from BOTTOM COWL ASSEMBLY AND SHIFT LINKAGE. which goes into the shift shaft of the lower unit.

Is there something I'm missing that is needed to keep this shaft from moving up when trying to shift with the cable, or am I totally out to lunch and the problem lies elsewhere?

Don

Re: thunderbolt 500 please help with gear adjustments

As for the control box, I've had a closer look at it, and one of the cables is binding, (the cable that connect to the warm up lever) would you happen to know if it would be the cable for the gas or shifter? It would be logical for it to be the gas, but then again I'm new to this marine world...

Re: thunderbolt 500 please help with gear adjustments

Don;

Let's use the parts listing which better matches your s/n as I gave you in post # 9. If the upper shift rod is moving up, it may be that the spring 54 is not connected to the shift rod. If you look closely you will see that when correctly anchored the spring will also match the detents on the upper shift rod when the gears are selected. That spring keeps a download on the top surface of the swing arm of the shift rod and provides the positive feel (detent) when the spring is engaged in the swing arm slots.

http://www.crowleymarine.com/mercury-outboard/parts/395_13.cfm

Here is a link to the MerControls Newest Manual. Large file but when downloaded, your box is probably the first one. You will see that there are two cams in the box, the throttle cam and the shifter cam. If your box is mounred on the right side of the boat, then the outermost cam to the right is the throttle cam, connected to the throttle cable. The innermost cam to the left is the shift cam and cable.

http://www.4shared.com/office/aYv2iNTC/merc_controls_newest_manual.html

Gerry

Re: thunderbolt 500 please help with gear adjustments

Hi Gerry,

Thanks a million for all of your advices, having a spring holding down the shift rod makes a lot of sense. But I'm not sure where this spring is suppose to be hooked on. Looking at the diagram it only shows the spring on the side of the shift rod. Would you be able to point me in the right direction as to where this spring is suppose to go?

My apologies if my posts aren't always clear.

Don

Re: thunderbolt 500 please help with gear adjustments

Don;

Here is a link to a picture of the exhaust plate item 35, with the spring installed but the upper shift shaft has not been installed yet:

http://img38.imageshack.us/img38/4271/img2919py.jpg

Here it is with the shift rod installed and you can see clearly how the spring rides on top of the shift shaft swing arm and contacts the selected gear detents in that arm:

http://img805.imageshack.us/img805/9798/img2920y.jpg

Hope that helps to clear it up.

Gerry

Re: thunderbolt 500 please help with gear adjustments

Hi Gerry,

The pictures are worth a thousand words like they say.

The first picture you sent me would make a lot of sense, but the second one is different from my outboard setup. I've enclosed a few pictures of the setup. I think I would need a different spring and/or gear detent if any.

You can barely see the rod connection to the shift rails, sorry.



Second part of the one piece that connects to the rod going to the shift rail.






I hope that I'm not too confusing

Don

Re: thunderbolt 500 please help with gear adjustments

Don;

Pictures aren't making much sense. Do you have a spring setup? My engine is a 1968 and yours should be very close to the same setup.

Gerry

Re: thunderbolt 500 please help with gear adjustments

Gerry,

This is the way I bought the motor, I've looked for a spring and I can't see anything, only the nut that seems to be at the same place as the one in your pictures. It would make sense for it to have a spring which would keep the shaft down. But now that your telling me that the pictures don't make any sense, I'm not sure what to think. The serial number I gave you is the one on the front bracket of the engine....

Could it be that some parts have been swapped from one year to the next? i know very little about the outboard except that the engine runs good, I only need to figure out the gears.

Re: thunderbolt 500 please help with gear adjustments

Looking on ebay I found a shaft that looks quite a bit like the one I have.

http://www.ebay.ca/itm/MERCURY-MARI...sories_Gear&hash=item564bc374cc#ht_500wt_1414

Do you think if I could find a parts list for any one of these outboards that I'd be in business?

Re: thunderbolt 500 please help with gear adjustments

No, don't go changing things for the unknown.

If you open either of the pictures I sent you and doubleclick on them to blow them up, you can see where the spring is held in place by the nut. This is directly aft of the spring pins which hold the cables in place. Is that nut there and just the spring is missing. If that is the case, we can get you the spring.

Secondly, are you saying that the swing arm on top of the shift rod (with the three detents) on yours is different than mine?

Gerry