First start up difficulty

[quawk]

I am a new member and this is my first post on this board. Am in the process of trying to start my bike for the first time in a long time since purchasing. I have poured over most, if not all, of the posts related to this but am still having problems. A little history of what I've done prior to trying to start as per suggestions found here on the forum. Drained sump oil and metering tank oil and filled with Castrol GTX. Drained and replaced trans oil with Rotella 15w 40. Have removed, disassembled and thoroughly cleaned the carb ultrasonically. Reassembled, closely following the instructions and photos found here. (The thin needle is present in the non-removable jet/passage) Have tested the plug spark with the plug removed and grounded to the case while spinning the starter. It consistently has very strong spark. Have checked the static timing as suggested listening for the plug to snap while viewing the timing marks through the timing cover near the top of the case. It is within timing range. "Wants" to start meaning sometimes will start and run for possibly a few revolutions. A couple of questions, the owners manual says to keep the clutch lever squeezed in while trying to start "electrically", meaning with the starter. I have not seen this mentioned here on the forum and why would this be necessary? Also I have the tank off the bike while trying to start because I understand about the vacuum operated fuel petcock and its' being prone to failure. I am temporarily using a small plastic tank from a snow blower. I have a Vise-grip pinch off tool on the fuel line between the tank and the carb to shut off fuel flow. If I leave the fuel flowing, fuel will sometimes start dripping out of the carburetor. I have rebuilt enough carbs to understand the float, normally. should shut off fuel flow once the bowl fills, and with the original tank, fuel will only flow when the engine starts(vacuum present). While the carb was apart I checked closely for proper operation of the float and the needle and seat set. Any ideas on what I'm missing here and why fuel may be leaving the carb while sitting? I welcome any response, info, or advice.

[wayne]

You've done very well and thank you for taking the time to read and apply before asking questions.

There's no need to keep the clutch squeezed in if you're in neutral. There's no electrical cut out as you sometimes find on old Kawasakis (for example). I'm wondering if it's just Suzuki's legal team doing a 1975 "cover their arse".

You probably have already but here's a tip that's worked despite what appears to be a good spark. If you're using a genuine plug, fit a new one. Once you get the bike running and properly set, they don't seem to suffer this anymore. One of my bike's records so far is a near instant start after 6 years on museum display. However, in the distant past when it hadn't been gone over, starting more than a month apart was always a drama and more than once the plug thing worked (this is fairly common).

As for leaking fuel if you don't shut off the fuel line, many of them do. I've replaced the needle and seat at least twice on my rider along with petcock rebuilds. I gave up and clamp off the fuel using the surgical version of your vise grip tool.

Also, I'm sure you're not doing this but remember every time you give that throttle a turn you're pumping fuel into the secondary throat. I've seen one of the best running RE5's embarrassingly fail to start after a show because the owner had done too many throttle twists showing off his pride and joy to the interested public.

[quawk]

Thanks for the response, suggestions and info. I'd assumed that keeping the clutch squeezed was a redundant safety measure in addition to stressing the point of having the bike in neutral when starting so it wouldn't take off unexpectedly were it to start in gear. I do happen to have one new original spark plug that came with the bike when purchased. I have not tried using the new plug since the spark was so strong with the plug that is currently in the bike, and the cost and rarity of finding/buying a new original plug. But, per your advice I will certainly try it and keep my fingers crossed. Although I don't like the thought of fuel leaking out the carb, hearing that it happens to others makes me feel like at least I don't necessarily have some uniquely weird or odd problem with this carb. I have read the post(s) about avoiding twisting the throttle when trying to start because of the accelerator pump squirting unwanted additional fuel, so no, I haven't been trying to use the throttle.

[timpa136]

Before you get too involved,it sounds like this bike has sat for such a long time that

compression should be confirmed. Gas gone bad and allowed to sit will stick the seals.

You have not mentioned the coolant condition in your posts or the spark plug appearance.

Here is hoping for the best outcome.

[quawk]

Thanks for the response timpa136. Had done a compression check before trying to start with a good quality Milton conventional compression tester. It shows 130 lbs. From other posts I have seen here that looks to be pretty good. Spark plug appearance shows the insulator around the center electrode to be darkened somewhat, not sooty looking, and sometimes when I remove it after trying start it looks slightly wet with what may be fuel but not necessarily oily. Last night, as per Wayne's suggestion I did try the one new plug I have and was able to get it to start for a slightly longer time. Before it would start for a few revolutions, and after trying the new plug it would sometimes start and run for a few seconds. Not much better, but better. I have just now checked the coolant and there is not enough coolant showing down the filler neck to even pull a sample into an anti-freeze tester. I know that's not good, but didn't think being low on coolant would impact being able to just get it to start and run for a minute or two. I saw no signs of coolant in the sump oil when I changed it.

[HGH 770N]

Iff you needle/seat valve is passing and over filling float bowl this not only show its self by dripping inside carb fuel could also pass between jets try through float bowl gasket.
Fuel rises on top of the gasket inside the bowl that would cause starting issues.
Tell tail signs are wet gasket joint around outside of float bowl.
A fix if you haven’t new gasket or valve maybe drain carb (removing 12mm brass plug bolt)
Let drain and evaporate for a while.
Spin the engine over with out spark plug to clear excess fuel.
Check with alloy inlet horn removed that the choke opens and closes (Flapppng) automatically when engine turns over.(the choke diaphragm could be in active and will flood engine)
I had a bike with me that wouldn’t start or run well and problem was the air filter he had bought from the US .
The bike should start easily with out air filter or the intake removed.
Good luck.
Just my experiences .
Rog

[quawk]

Thanks for the advice HGH770N. The carb doesn't appear to be wet around the float bowl cover gasket. In all starting attempts, the aluminum inlet horn/tube has been removed to rule out air filter issues, and the factory tank has been removed and am using a small plastic temporary tank from a snow blower with a pinch-off tool for a fuel shut off. The choke does "flap" as you describe while spinning the engine. I couldn't imagine having to have the air filter and inlet in place for it to start, so I'm glade you indicate it doesn't need to be. A question I have is do the fuel inlet needles from the factory normally have the metal tip. In another post about carb disassembly it shows a needle with a viton tip which I assumed was an after market needle. My needle and seat set both look to be in excellent shape, but if it's leaking I understand I should try a replacement. Are they commonly available? By the way I'm a Roger, also.

[hudson]

 I have dealt with a mystery leaking needle and seat and it was the red sealing washer that seals the seat to the carb. top. It looked perfect even with magnification. Replaced it and problem solved. All of the stock needles I've seen have been metal tipped and after market have been Viton tipped. The hard part to duplicate with after market is the hole diameter in the seat. 3mm for stock and all the aftermarket ones I have come across have been 2mm through hole.

Brian

[quawk]

Thanks hudson. Your response about something like the sealing washer causing the leak is what's frustrating about these bikes to someone that has wrenched on a wide variety of machines for many years. The small things can be the difference between starting or not. On so many other conventional engines if you could get it close, you could at least get it to start and then go from there. Not to oversimplify but this is still just a gas burning, spark ignited engine, but seemingly is very sensitive to the little details to make it run, or run properly. I'm still learning. Serenity Now!

[timpa136]

Oct 31, 2021 15:33:21 GMT -5 quawk said:

Thanks hudson. Your response about something like the sealing washer causing the leak is what's frustrating about these bikes to someone that has wrenched on a wide variety of machines for many years. The small things can be the difference between starting or not. On so many other conventional engines if you could get it close, you could at least get it to start and then go from there. Not to oversimplify but this is still just a gas burning, spark ignited engine, but seemingly is very sensitive to the little details to make it run, or run properly. I'm still learning. Serenity Now!

    If I may add from my own experience, the low coolant could be a problem. If you haven't already, measure how much distilled water you need to add to see it in the filler neck. Low level  and/or weak coolant has  additional concerns . If you have a radiator and cap pressure tester, apply some gentle pressure on the cooling system. In the absence of a tester, one thing you do not want to observe is bubbles when looking down the filler neck when starting. Hoping for a good outcome.

[quawk]

Upon trying to add coolant, it looks like it leaks out the short hose between the filler neck and the radiator neck. Seems like I have seen in another post that this hose is prone to splitting and the ends of the hose are different diameters and therefore hard to find a replacement/substitute.

[HGH 770N]

3 mm needle/seat valve seem to still available in the US and listed on eBay.
I too have had fuel seeping past the washer down the thread .
Take care when replacing as the valve has a shoulder on it and a standard 10mm washer that fits thread doesn’t fit over the shoulder and prevent sealing .
The small coolant hose to the expansion tank is prone to perishing and even blocking up where connected to the rad .
Take care on removing as the connection pipe have been known to brake off.
The coolant level is only about 1/3 .
Check the rubber on the pressure cap is not hard or perished as this can cause coolant to vent out through overflow pipe .
Iff coolant it leaking inside chamber this could be just plate sealing seals or as serious as a crack in the chamber.
Hope it’s not the latter.
Rog

[quawk]

Thanks HGH770N. What do you mean by the coolant level is only about 1/3?

[HGH 770N]

With tank removed see level of coolant in expansion tank 1/3 .
Over fill it and when thermostat opens expansion will over fill the tank and push coolant out of the neck overflow pipe.
Looking at level as per manual through the top is easier to relate to with the petrol tank removed.
If coolant has been drained from the whole unit when refilling take care as the system can get air lock .
There a small whole in the top flange on thermostat that it easily blocked and then creates a air lock until it opens at temperature .

[timpa136]

Two more things to check ,the later one is very rare.

Remove the port valve cover and make sure the cable action is free and valve closes.

Secondly, recheck timing and rotate engine around again and recheck that you have spark

there as well.

Tim