1976 550 oil leak and unsteady idle

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rderrick121
Posts: 45
Joined: Thu Nov 29, 2018 10:31 pm

1976 550 oil leak and unsteady idle

Post by rderrick121 »

Hello all, I finally got my 550 up and running, I am getting an engine oil leak although I cannot seem to find it, are there any common places? It seems up higher than the drain plug but it could be it, I didn't change the crush washer.. it leaked before a bit but I assumed it was the clutch cover gasket which I have already replaced. (what is the best way to get the ignition wire through the new gasket? I cut it on the top where there is no oil and added extra gasket maker.) It is not a fast leak, only a drop or 2 an hour but is a leak :?

Also, when I start the bike up cold and it warms up it idles nice where I have it set. After I run the bike hard, down the highway or really push it down the road, when it returns to the idle position it idles quite high for a minute or so until I either reset the idle screw or it just comes back down (causing it to idle too low and stall), what could cause this?

Thank you!
barney01
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Joined: Wed Sep 26, 2012 7:33 pm
Location: Prestatyn.Wales

Re: 1976 550 oil leak and unsteady idle

Post by barney01 »

Firstly good news you have the bike on the road. You need to determine if it is transmission oil or 2T engine oil that is leaking. You need to thoroughly wipe the crankcase clean and lay white paper under the bike. Hopefully this will give you an indication.
Does it continually weep or stop after a while?
I do the same as you with ignition wire through gasket.
The symptoms you describe with running problems sounds like an air leak. How soft are your carb rubbers? Try starting the engine and spray starting spray or WD40 around each carb to cylinder rubber in turn. If the revs rise you have a leak.
NO SMOKE .......NO POKE
rderrick121
Posts: 45
Joined: Thu Nov 29, 2018 10:31 pm

Re: 1976 550 oil leak and unsteady idle

Post by rderrick121 »

Hi Barney, the oil that is leaking is the regular gear oil not 2t, I will try this.

As far as the rubbers, the boots on top of the carbs are new, the thick ones that the carbs go into are old but in pretty good condition, it runs fine its only when I am hard on it and come off after that this high idle condition lasts but I will also check for leaks there. On the carb that is farthest to the right there is that small bolt that allows you to see in and see the dot on the slide of the carb slide, mine is wayyyy off, what's the deal with that? Could my carbs be out of sync/when reinstalling them I just used a wedge to verify all the slides lifted evenly/at the same time. :shock:
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canaletto5
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Location: Derbyshire

Re: 1976 550 oil leak and unsteady idle

Post by canaletto5 »

Hi

The dot on the slide is to synchronise the oil pump setting. When it is visible at the top of the hole, the two marks on the oil pump lever and mount should be aligned. Kev
barney01
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Joined: Wed Sep 26, 2012 7:33 pm
Location: Prestatyn.Wales

Re: 1976 550 oil leak and unsteady idle

Post by barney01 »

The carb rubbers that connect to the cylinders are the ones that will leak and cause the uneven idle. Through age and heat they become hard and don't seat properly allowing air to get in. New ones don't come cheap but they are Vital to the smooth running of the engine. Also if you continue to run it like this, because the mixture is lean you risk overheating the piston crown.
If you look at the end of this video you can see how to use the sight hole to set the oil pump as Kev said.
https://youtu.be/jJGl_hab3Bg
NO SMOKE .......NO POKE
rderrick121
Posts: 45
Joined: Thu Nov 29, 2018 10:31 pm

Re: 1976 550 oil leak and unsteady idle

Post by rderrick121 »

Hello all, sorry for the delay, a change in projects at home, school and work has had me busy so the 550 got pushed back. I finally have it up on the stand as of last night, cleaned it up as best I could and found that I am not seeing anymore gear oil although I have found oil like stuff coming from elsewhere so I will start with that.. I pulled the exhaust system off of the bike to see the underside more clearly. After checking the oil levels I have a good bit of gear case oil and the 2 cycle oil is mostly full I kicked it over a couple times to move stuff around and it actually fired up.. I immediately shut it off.However, I did notice oil coming from the far left cylinder exhaust port (sitting on the bike looking down at the motor left) I will attach pictures. I see that there are crush washer like seals that seal the header to the block and I am wondering how deep should these be in the heads? The far right cylinder appears to not have one while the other 2 do. Today there is oil directly dripping from the far left exhaust port (about 5-6 drips on the floor in a very small puddle) Please share your insight. Thank you, Richie
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barney01
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Joined: Wed Sep 26, 2012 7:33 pm
Location: Prestatyn.Wales

Re: 1976 550 oil leak and unsteady idle

Post by barney01 »

As the bike has been sat for a good while it is likely that the oil pump banjo valves may have been weeping 2T oil into the cylinders. This is not ideal but very common. The good news is the bike started and was not so flooded with oil to cause Hyraulic lock. This is where the piston descends under power and because of the oil has nowhere to go it bends the conrod.
FIRST job is remove the little SRIS valves and tubes from the front of the engine over night to allow any excess petrol and oil to escape. Then put them back in.
The exhausts all have a seal that fits into the cylinder head. I use a small leccy screwdriver to edge them out.
They do sit quite deep.
What this engine really needs is a good long hard run to blow all the crap out :D
Here is the exhaust gasket
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NO SMOKE .......NO POKE
rderrick121
Posts: 45
Joined: Thu Nov 29, 2018 10:31 pm

Re: 1976 550 oil leak and unsteady idle

Post by rderrick121 »

Hello Barney, you are correct, I just pulled the SRIS lines and fittings out and each one had a good bit of 2 cycle oil that came out of both the case and line. I also pulled out my header gaskets, I got 5 gaskets out of the 3 ports so no wonder I was getting a little blow by... I will order new gaskets, any insight on where to get them without paying an arm and a leg in shipping? I am in the us and I think my part number is: 14181-34020.. Also, once I get the gaskets and when I am reinstalling the headers the part that the bolts go through to pull the pipe on to the head are threaded, where/how do I set these? I can screw them both completely off and hold it in my hand or on so that it fits onto the header pipe. Thanks again, also what's a "leccy screwdriver"??
barney01
Posts: 3118
Joined: Wed Sep 26, 2012 7:33 pm
Location: Prestatyn.Wales

Re: 1976 550 oil leak and unsteady idle

Post by barney01 »

You can get your gasket here:
https://www.partzilla.com/product/suzuk ... 6e37d85ae2
So when refitting the exhausts clean out the ports where the gasket sits as best you can. Fit just one gasket to each hole :lol:
Next use a little copper anti seize grease on the thread of the muffler screw the collar onto the end as far as you can. Fit the end of the pipe into the hole and screw the collar towards the cylinder but not all the way leave a big enough gap so that as you tighten the retaining bolts the gasket will collapse sealing the pipe.
There must be a gap of 2mm between the collar and the cylinder so that it can flex whilst the motor runs. You may have to do it up and take it off again till its right.
NO SMOKE .......NO POKE
rderrick121
Posts: 45
Joined: Thu Nov 29, 2018 10:31 pm

Re: 1976 550 oil leak and unsteady idle

Post by rderrick121 »

Hi Barney, I ordered the rings. While waiting is it safe to gently run the bike on the stand not for long but to search for any other possible leaks?
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