Honda-SOHC

SOHC.co.uk Forums => CB350/400 => Topic started by: Dolomite_ on June 22, 2024, 07:48:12 PM

Title: First start up after rebuild help. Possibly points not timed correctly
Post by: Dolomite_ on June 22, 2024, 07:48:12 PM: Started it up today and after a few tries with the starter and then some more with the kick start it did eventually fire up for about 10 seconds, but then it sputtered out.

Im not sure if maybe the carbs are a bit bunged up, but before storing them I did drain them completely. So I think they're fine.

There is fuel, there is air and there is a spark on plug 4, Ive not checked the others yet as the battery went low.

I did set up the points today and followed 2 videos (https://www.youtube.com/watch?v=58m84jkaAsE&t=783s (https://www.youtube.com/watch?v=58m84jkaAsE&t=783s) and https://www.youtube.com/watch?v=3933ouJ1wrI&t=615s (https://www.youtube.com/watch?v=3933ouJ1wrI&t=615s)). It was fine setting the gaps, just took a few tries. I did have some issues with setting the points. I couldn't replicate exactly how they did it in the video. When I had the switch to RUN it didn't seem to make a noise on my multimeter even when the points were touching on 1/4 with the timing mark on F but it did literally spark at the contact point when I moved the points disk back and forth. When setting the points for 2/3 I didn't seem to get noise on my multimeter at all.

When I set the switch to OFF and touch both points the multimeter makes a noise but as soon as I switch it to run it doesn't make a noise.

Is there a better way to set the static points?

Other than that it seems to be ok, the oil light went out and I also got a few splats of oil come out of the tappet cover holes.
Title: Re: First start up after rebuild help. Possibly points not timed correctly
Post by: McCabe-Thiele (Ted) on June 22, 2024, 08:58:03 PM: When I did my 500 recently I rotated the crank with the plugs out using the kick start - your trying to find the point where the points are fully open. It pretty much coincides with the tang part of the advancer being in the middle of the top case mark. It might be a tad either side if you have aftermarket points.
Don't turn the crank anti clockwise and I would avoid using the tempting big nut on the end of the crank.
I rotated my crank at least 4 or 5 times on the 1/4 points - repeat for 2/3. I used a bulb for the static timing. Once running dynamic is straight forward.
Title: Re: First start up after rebuild help. Possibly points not timed correctly
Post by: Dolomite_ on June 23, 2024, 11:41:50 AM: So ive, re adjusted the gaps like Ted said, at the little tang bit. And managed to find somewhere that sells a light up circuit tester on a Sunday :D. I have no idea if its possible but the points seem to be as it they are 180 degree out of sync or something. When 1/4 is open 2/3 lights up and visa versa. But it also isn't near the F mark at all, and when I move the points disk to advance and retard them they don't turn out.

Have I completely messed something up with the points? Is there anything that I might of got wrong that could make them out by 180 degrees?

1/4 points
(https://i.imgur.com/xK921ia.jpg)

2/3 points
(https://i.imgur.com/QA3VRpX.jpeg)
Title: Re: First start up after rebuild help. Possibly points not timed correctly
Post by: K2-K6 on June 23, 2024, 11:46:12 AM: For 180degree out, you could have the cam on the advance and retard spindle "flipped" as that just swaps them to that effect.
Title: Re: First start up after rebuild help. Possibly points not timed correctly
Post by: Dolomite_ on June 23, 2024, 12:15:12 PM: Quote from: K2-K6 on June 23, 2024, 11:46:12 AM
For 180degree out, you could have the cam on the advance and retard spindle "flipped" as that just swaps them to that effect.

I'm don't think that would be the case for me because I've not had the points cam with the weights apart. Unless it can turn full by itself while still together?
Title: Re: First start up after rebuild help. Possibly points not timed correctly
Post by: Dolomite_ on June 23, 2024, 01:21:09 PM: After taking the points disk off have a fettle and putting it back on, I was able to get them set correctly. And it started up pretty much straight away with no choke! Exhaust is a little blowy because the clamps arent tight but other than that it seems good. The oil light went out after a couple of seconds just cranking it over and when actually firing it up I got some oil splats of my tissue paper from the tappet covers.
Title: Re: First start up after rebuild help. Possibly points not timed correctly
Post by: McCabe-Thiele (Ted) on June 23, 2024, 03:44:16 PM: Just as an aside the bulb illuminates when the points start to open. This only works if the points base is earthing on the crank case in the first place iirc & if that makes sense.
Title: Re: First start up after rebuild help. Possibly points not timed correctly
Post by: Laverdaroo on June 24, 2024, 09:47:21 PM: Watch this, this will explain it better for you.

Just follow the steps, itâ€™s dead easy. Might be worth while you looking at the tappet set up film he does also.

Keep at it, youâ€™ll get there

https://youtu.be/DR2a99uC9W4?si=r7mX0UORB-zLc7Kc

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Title: Re: First start up after rebuild help. Possibly points not timed correctly
Post by: Laverdaroo on June 24, 2024, 09:48:18 PM: https://youtu.be/3933ouJ1wrI?si=BnYufQA3rTch-WAY

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Title: Re: First start up after rebuild help. Possibly points not timed correctly
Post by: Dolomite_ on June 24, 2024, 09:51:52 PM: Laveradoo, theyre some of the videos I found. Once I go the points triggering when they should it was pretty straight forward to follow the videos.
Title: Re: First start up after rebuild help. Possibly points not timed correctly
Post by: Laverdaroo on June 24, 2024, 09:57:07 PM: No worries, you never know bc whoâ€™s watched what and these are just good vidâ€™s to follow.

Cool beans

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