C40TLRX - Scratching my Head, Questioning Manual

[a387673]

I'm not much of a mechanic, and rely heavily on the manual (SELOC), but here are a couple of examples of items I've run across in the manual that I am questioning:

1- On general compression test steps, when moving throttle to wide open. manual says to advance "the throttle in order to get the shifter into gear", then proceed with compression checks. My starter does not operate with the engine in gear.

2- On idle speed adjustment, one step reads "Loosen the throttle lever screws that secure the upper and middle carburetors...", followed by turning the idle adjustment screw to set the idle. Since my idle adjustment screw is on the middle carb, for which I just loosened the throttle lever screw, how can this have any impact?

I'm sure I'm just missing something stupid, and I am frustrated already with the motor. Thanks for any guidance on these specific steps, as to the accuracy of the manual or where I'm missing something.

[TownsendsFJR1300]

I'm not much of a mechanic, and rely heavily on the manual (SELOC), but here are a couple of examples of items I've run across in the manual that I am questioning:

1- On general compression test steps, when moving throttle to wide open. manual says to advance "the throttle in order to get the shifter into gear", then proceed with compression checks. My starter does not operate with the engine in gear..

Your correct, the manual is NOT. It won't crank in gear.

Pull the lever/push the button, etc to get neutral AND be able to crank the engine over. To get a fast idle..

You might want to also (if equipped), pull the black safety clip on the ignition. You can still spin the engine over but it kills the spark.


As for your idle set up, I'm not familiar with it, someone else will chime in to help.

99Yam40 will likely know the procedure as he has very likely the same engine.

http://www.boats.net/parts/search/Ya...TOR/parts.html

[boscoe99]

The compression test should be performed with the motor hot, the battery fully charged and the throttle wide open. Motor should be in neutral. Insert the gauge. Crank the motor until the pressure stops rising.

I don't have a Seloc manual. I suspect what they may be saying is to use the device (neutral shift button) that prevents the motor from being shifted into gear when the throttle is placed in the WOT position. As you have found out, if the throttle handle is in gear then the motor won't crank.

Does the Seloc manual have photos? Photos in the Yam SM make it a bit more clear. Don't worry about what is being done or how it is being done. Just follow the procedure.

[99yam40]

I have found the service manual I have is wrong on some things, just using common sense works.

on link and sync that C40, I asked Rodbolt some years back about the procedure I had and it was way wrong. do a search of my threads to find it. I think it was on this web site. if not I can look to see what I can find
from what I remember you loosen the linkages close all the throttle pates completely ,lock them together , and the adjust the idle screw some for start up and then adjust to get the RPM you want

as I have said in the past on the 2 stroke's compression test you do not need to open the throttle , but it is a good idea to to do if doing 4 strokes also. get in the habit of doing it on all motors

[a387673]

Thanks

Thanks, Guys, for the helpful info. One item I need clarity on is "turning the magneto control lever" in the process of checking/adjusting the throttle linkage. As the throttle cable is not disconnected at this point, does it seem likely that the only way to turn the magneto control lever is with the throttle control?

99, I found the old post you mentioned, I knew I had seen it before. Thanks. Unfortunately, I think I am running into the problem you had with the throttle linkage adjustment, where the timing is out of spec (too retarded, based on idle mark on CDI) when following the adjustment procedure in the manual. I hope a new CDI unit is not in my future.

[99yam40]

when I hear or read magneto control lever I think of the old manual linkage for timing

not sure what you are getting at there.
there is a linkage to the wiper on CDI that has marks for idle and WOT timing settings, are you asking about them?

[a387673]

CDI, LInkage

99, Here (pic, if upload worked) is what they are calling the magneto control lever, in the throttle/CDI/magneto linkage. From what I can see, the throttle control is the only way to "turn" it with the linkage attached....?

Coincidentally (perhaps), my timing specs/set-up are identical to what you posted years ago, in relation to the CDI which I think you ended up replacing. I suppose a common fault might explain that, which of course would point to me needing a replacement also.......

[a387673]

"Nervous" Timing Mark

Perhaps simply due to roughness in the idle, the timing mark appears to jump around in a range of maybe 4 degrees (2* +/-), or a little more. Would this be normal, or a "symptom" that points to something in particular (cause or effect, in other words)?

[99yam40]

You can disconnect the throttle cable at the motor and then move the linkage by hand at the motor
or move the con*****er with the cable hooked up.
either way you are just trying to set the pointer to the marks.
you still need to be checking the timing with a light afterwards.
as you know I could not get mine to work properly until I put a new CDI on

[99yam40]

Just saw your last post.
I do not know for sure.
have you tried hooking the timing light up to the other plug wires to see if they are doing the same thing?
may need to put some marks on flywheel to see

[boscoe99]

The SM and the parts catalog show the magneto control lever with an adjustment screw on the end. I don't see that in the photo.

99Yam, does your lever have the screw or not?

[99yam40]

raining to hard to even think about going out to check right now

[99yam40]

looking at my manual I would say yes it does have that screw as that is part of the adjusting I did on mine trying to get the timing in spec before I replaced my CDI

not sure is his pic is what he has or he just found a pic to show what part he was talking about.

he was using the correct name I just did not remember it being called that. been a few years since I played with that part of procedure

[a387673]

Lever, CDI

Thanks again, Guys. The pic was a dis-assembled part someone was selling, mine does have the adjustment screw.

99, the timing marks for #s 2 and 3 do the same thing (jumping back and forth) when idling.

Like yours, 99, the full-retard stop setting does not seem to be compatible with the idle timing indicator on the CDI. Either the plastic link threatens to come off the end of the control rod, and/or the pointer on the CDI is not properly aligned to the idle mark when the full-retard stopper and timing are set to spec.

In addition to other throttle linkage adjustments, there would seem to be two opportunities for adjusting that my manual ignores. In the attached pic, I circled (green) the nut which holds the pointer on the CDI. Can this be removed and replaced in such a position that the magneto rod link stays firmly connected, and the pointer lines up to the mark, with correct timing?

Also (and you guys may have alluded to this, but my manual doesn't), the magneto control lever can be decoupled from the accelerator cam (bolt circled red), which would appear to allow for adjustment between the carbs and the idle stop screw and CDI linkage/timing.

Thanks for all the feedback and advice. I'm learning, even if I'm not any closer to resolution.

[boscoe99]

Thanks again, Guys. The pic was a dis-assembled part someone was selling, mine does have the adjustment screw.

99, the timing marks for #s 2 and 3 do the same thing (jumping back and forth) when idling.

Like yours, 99, the full-retard stop setting does not seem to be compatible with the idle timing indicator on the CDI. Either the plastic link threatens to come off the end of the control rod, and/or the pointer on the CDI is not properly aligned to the idle mark when the full-retard stopper and timing are set to spec.

In addition to other throttle linkage adjustments, there would seem to be two opportunities for adjusting that my manual ignores. In the attached pic, I circled (green) the nut which holds the pointer on the CDI. Can this be removed and replaced in such a position that the magneto rod link stays firmly connected, and the pointer lines up to the mark, with correct timing?

Also (and you guys may have alluded to this, but my manual doesn't), the magneto control lever can be decoupled from the accelerator cam (bolt circled red), which would appear to allow for adjustment between the carbs and the idle stop screw and CDI linkage/timing.

Thanks for all the feedback and advice. I'm learning, even if I'm not any closer to resolution.

Red and green are just pivot points. Adjustments are made elsewhere.

Try following the following two procedures. In the order provided. Don't be making any adjustments if the marks line up as they are supposed to.