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A couple of 'issues'

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modelman
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A couple of 'issues'

Post by modelman » Thu Sep 10, 2015 7:47 am

Ok, Finally put some fuel in after what's probably 30 years of being seized solid, made a complete new wiring-harness, etc,etc, & WOOSH, fuel everywhere!!
Numbnuts here somehow managed to put the petcock together arse-about-face, sorted that, & both carb-bowls were leaking like a pin-cushion around the drain bosses, so unfortunately I had to JP Weld the brass drain screws all around that area, not the end of the world & I can live with that.

Tried a second time, gingerly fuelled her up again, no leaks this time!!

Ignition-on, choke on, turned her over, Plop, plop, plop, zilch!!
Choke off, pressed the button & she burst into life, ran beautiful & smooth, BUT I couldn't see the tacho as it was up on the bench, but it ran at a constant 2000 or so revs, it DOES throttle up & down, but no tick-over at all.

SO, issue-1, the throttle cables are backed right off, a bit sloppy in fact, how do I lower the RPM's?

Issue-2, this ones a bit naughty, there's an oil leak from the head-joint, directly under the LH carb, & it runs down the fins & drips under the exhaust outlet & onto the starter motor. The mating surfaces LOOKED fine & all new gaskets, dare I risk winding the studs a bit more??
There was 2 O-rings at the head-gasket, but I thought they went at the 2 outer-front studs?This leak appears at the rear-second stud area.

Looks like I might be pulling the engine out again.
GSX1400 Red/silver
GSX1400 Blue
GS1000G
Brockhouse Corgi
CB77
CA77
T140
BSA 250

I DO have to grow old, I DO NOT have to grow up.

LOUD MOUSE
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Joined: Mon Aug 15, 2005 8:23 am
Location: KERRVILLE, TEXAS

Re: A couple of 'issues'

Post by LOUD MOUSE » Thu Sep 10, 2015 9:22 am

Lower the slides.
Or some times balance the slides to each other. .............lm
modelman wrote:Ok, Finally put some fuel in after what's probably 30 years of being seized solid, made a complete new wiring-harness, etc,etc, & WOOSH, fuel everywhere!!
Numbnuts here somehow managed to put the petcock together arse-about-face, sorted that, & both carb-bowls were leaking like a pin-cushion around the drain bosses, so unfortunately I had to JP Weld the brass drain screws all around that area, not the end of the world & I can live with that.

Tried a second time, gingerly fuelled her up again, no leaks this time!!

Ignition-on, choke on, turned her over, Plop, plop, plop, zilch!!
Choke off, pressed the button & she burst into life, ran beautiful & smooth, BUT I couldn't see the tacho as it was up on the bench, but it ran at a constant 2000 or so revs, it DOES throttle up & down, but no tick-over at all.

SO, issue-1, the throttle cables are backed right off, a bit sloppy in fact, how do I lower the RPM's?

Issue-2, this ones a bit naughty, there's an oil leak from the head-joint, directly under the LH carb, & it runs down the fins & drips under the exhaust outlet & onto the starter motor. The mating surfaces LOOKED fine & all new gaskets, dare I risk winding the studs a bit more??
There was 2 O-rings at the head-gasket, but I thought they went at the 2 outer-front studs?This leak appears at the rear-second stud area.

Looks like I might be pulling the engine out again.

modelman
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Posts: 222
Joined: Wed Jun 24, 2015 2:27 am
Location: Yorkshire, UK
Contact:

Post by modelman » Thu Sep 10, 2015 10:34 am

Yes, I realise that, but they are as low as I think I can get them, they are resting on the stops at the bottom, & they are crudely 'balanced' with a bit of 2mm wire in each throat & both move exactly together when the twist-grip is opened.
I can hear them both 'tap' at the bottom when closing.
Overall, it can't be far out as its running before I release the starter-button!
I have a set of 4-cylinder carb-balancers for the big bikes, but cannot find any vacuum nipples to hook the pipes to.
It throttles up & down fine.
If the ARE bottomed-out, what do you suggest I try next?
GSX1400 Red/silver
GSX1400 Blue
GS1000G
Brockhouse Corgi
CB77
CA77
T140
BSA 250

I DO have to grow old, I DO NOT have to grow up.

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PhilD
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Location: Leeds,UK

Post by PhilD » Thu Sep 10, 2015 12:24 pm

Hi modelman,
Good to hear that the bike is running. It's unusual for these engines to start easily without choke especially at Yorkshire temperatures which suggests that it's running rich. Suggest you double check float levels and that air screws are at one to one and a half turns out as a starting point. The other cause could be an air leak at the inlet manifold, did you replace the O rings on both sides of the Carb insulators?
With regard to your left sided oil leak I wouldn't rush into a strip down. I assume you're certain that it's leaking from the head / barrel interface and not running down from the tacho drive cover. I had a small leak from the right front side on starting up my recent rebuild which as you say is the common site. This was despite using a torque wrench and shop manual settings for the first time in forty years as I previously made do with a ring spanner and what felt right! After cycling the engine up to working temperature a few times and careful re torquing in between the leak has dried up. ( don't forget to re tighten the 6mm nuts adjacent to spark plugs afterwards )
Good luck,
PhilD
1964 CB72
1964 CB77

SMBH
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Post by SMBH » Thu Sep 10, 2015 1:33 pm

Hi Modelman for what it's worth I had a simler problem (one of many) with my 1964 CB77 at standstill reving up to say 4,000 and the engine not closing down when the throttle was closed so I took a look at the slides I have the brass ones with hard hared chromed I could see were they were rubbing on the carb so I took some 400 wet/dry and worked on them till they would fall in and out of the carb nice and smooth.

First do make sure the carb flanges are not bolted up to tight just nip the 10mm nuts up.

I understand this is a problem with the brass sildes Honda changed them to alloy I belive.

I know it's a bit crude to sand down the slide but it worked for me any way im not going to be doing a lot of miles so long term wear is not a problem well not at my age 71.

By the way the Keyster carb kit for the CB77 worked ok for me jets, needles, ect.

Good luck with the bike had mine 2 years now and cost me the earth to buy and repair and still not 100% right.

A very strong will to live helps.

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