1971 t 350 no start

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Maryland2stroke
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Suzuki 2-Strokes: 1971 t 350

Re: 1971 t 350 no start

Post by Maryland2stroke »

Yeah I didn’t use compressed air I did it the old school way wipe the oil off and blow through it with my mouth one side is open the other isn’t guess I should have done same thing with the other side lines just to see now I got to find we’re i put those extra oil lines thank you very much for your help I will post as soon has I get back to working on it
karl pa
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Suzuki 2-Strokes: GT
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Re: 1971 t 350 no start

Post by karl pa »

Maryland2stroke wrote: Thu Dec 24, 2020 2:32 pm I didn’t use compressed air
Maryland2stroke wrote: Thu Dec 24, 2020 2:32 pm blow through it with my mouth
I know some people that seem to get more pressure out of there mouth than out of a compressor :lol: (sorry I couldn't resist)
If the check valve ball is stuck, you might be able to free it with some wd40 or similar.
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Maryland2stroke
On the street
Posts: 13
Joined: Sun Dec 20, 2020 6:07 pm
Country: Usa
Suzuki 2-Strokes: 1971 t 350

Re: 1971 t 350 no start

Post by Maryland2stroke »

You ain’t the only one who knows people like that :) I will fill with some wd40 and see happens with it
Maryland2stroke
On the street
Posts: 13
Joined: Sun Dec 20, 2020 6:07 pm
Country: Usa
Suzuki 2-Strokes: 1971 t 350

Re: 1971 t 350 no start

Post by Maryland2stroke »

Hello to all so iv replaced my right side oil lines check valve was stuck I’ve replaced it with a good used set I was able to take the check valves out and clean and pressure test them I filled them with oil the best I could with a eye dropper now when the bike is running I get air bubbles in the lines my left side has no air when the engine is running I manual pump the oil pump I get nothing I opened the bleeder on top of the oil pump bleed it still the same. Shouldn’t engine vacuum take over when the engine is running and assist the pump?
karl pa
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Re: 1971 t 350 no start

Post by karl pa »

Maryland2stroke wrote: Sun Dec 27, 2020 2:58 pm when the bike is running I get air bubbles in the lines my left side has no air when the engine is running I manual pump the oil pump I get nothing I opened the bleeder on top of the oil pump bleed it still the same
Not sure I understand, is the oil pump actually pumping? Manual pump?
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Maryland2stroke
On the street
Posts: 13
Joined: Sun Dec 20, 2020 6:07 pm
Country: Usa
Suzuki 2-Strokes: 1971 t 350

Re: 1971 t 350 no start

Post by Maryland2stroke »

With engine running I move the pump arm what the throttle cable hooks to it is pumping but not much when I move the arm on the pump I can see the air bubbles go back and forth. I left the cap off the oil tank and left the lines loose that go to the engine still nothing has changed still same air bubbles in the lines left side lines are full no air strange thing is with engine running still smokes out the pipes I would think it would not do that crank case/transmission oil is full I don’t run it for no more than a minute I know can’t be good for the crank. Shouldn’t engine vacuum assist the pump ? Thanks
karl pa
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Re: 1971 t 350 no start

Post by karl pa »

Maryland2stroke wrote: Tue Dec 29, 2020 4:35 pm but not much when I move the arm on the pump I can see the air bubbles go back and forth
Is this while engine running
Maryland2stroke wrote: Tue Dec 29, 2020 4:35 pm strange thing is with engine running still smokes out the pipes
Did you recently rebuild bottom end ? did you oil bottom end when rebuilding ?
If so it will have oil in crank to push smoke out pipes, after a rebuild it will need a good run to clean all the smoke out.
You are right the crank won't like no oil, premix can help top end but won't help outer main bearings, center main bearing is oiled by transmission oil.
Not sure about engine vacuum pulling oil from pump.
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Maryland2stroke
On the street
Posts: 13
Joined: Sun Dec 20, 2020 6:07 pm
Country: Usa
Suzuki 2-Strokes: 1971 t 350

Re: 1971 t 350 no start

Post by Maryland2stroke »

The bottom was redone it has a rebuilt crank with new bearings / seals from Paul Miller from eBay. I put the engine together two years ago during the winter I got it done and running but never got back to it until a few weeks ago I know I pre oiled it when I put the engine together so I guess it could be just the assembly oil still burning off. transmission oil is still full from sitting 2 years . Another thing I did I have a universal radiator pressure tester tool it applies pressure to find leaks I used that tool in the oil reservoir pumped it up to 4 psi to see if I had leaks and to see if it would purge the lines with engine running pressure applied and pump held open it made no difference I did replace the seals in the pump when I built the engine. Thanks for the reply sure is beating me :roll:
karl pa
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Re: 1971 t 350 no start

Post by karl pa »

I am thinking you have a pump issue, pressurizing the oil tank should have purged the pump and lines. When I have a check valve stick open, oil bleeds through the pump and lines and fills crank while shut off.
when you pressured the oil tank, did you block the breather, just something to make sure is open when done.
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Vintageman
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Re: 1971 t 350 no start

Post by Vintageman »

When you remove the oil pump air bleed screw at pump, oil should come out, no air mixed with it. If air in supply line it may take a moment to prime. If no steady flow of oil comes out bleed hole, fix this first. Check for plugged line (remove from pump side and see if oil come out) This line, screen filter (If I recall), and tank should be cleaned.

Rebuilt oil pump- if you put seal in wrong or nicked it, will cause air leak or shaft was worn and you did not notice. Else pump is simple. The end cap with the O ring, if you over tighten (very small screws yes?) cap will bow and cause air leak I have done it. You may see oil leaking from pump area as well which is a clue about air leak somewhere.

The supply lines from pump to engine. If the check valve is stuck open air from engine push into lines causing air bubbles. Yes, if you put your mouth on the check valve you need to suck kind of hard (>3PSI) and you will just feel the valve crack open. They both should feel the same and make same sound. I use air but set to <+ 4PSI. If OK, Fill lines with oil and hang them up (checked valve down) to see if oil slowly leaks out: 24 Hrs. That is a different issue vs bubble....fills your engine crank case with oil and after setting - causes engine to smoke heavy (hard starting too) until you rev it up a few time while driving to clear the cases. The green police will put you in jail and throw away the key.

Those carbs. Yup they can stick WOT. Lovely 32mm carbs and make that bike unique experince. Over tightening nuts can causes it as you notices, but you need to tighten to low side of torque spec(fresh springy and sharp Lock washer too). You can take 220 grit working to 400 and sand the top 1/2 of Carb body where slide rides. Just top half so you don't cause too much air flow around slide small throttle opening. Maybe 5-20 360 degrees turn with 220 in enough usually. finish with 400. The bodies can be oxidizes over time. Check slides for rough areas and repair those. Next be sure the Idled Adjustment Rod is not bent or has burs (It will from use) or Twisted 180 degree when you install slide into carb body :shock: . That will cause the slide vii it pass through hole for the rod to bind to the rod and hang up. These I recently bought from Suz and were still available and inexpensive.

Spend the ~$100 and get a used T350 air box .Buy new Y boot (old ones are usually tried out, but heated you may get it to work big PIA) and new air filter if needed and you got the coin. BE SURE IT IS T350! Not GT250 or T250. The T350 air box has larger air passages to feed dirty side of filter and if 250 box with smaller passages I am sure it will not have the top end.

Enjoy the bike. The T350, IT is one of my favorite bikes to drive even at 315 ccs stock bore.
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Suzukipilot
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Suzuki 2-Strokes: 1970 T350 II

Re: 1971 t 350 no start

Post by Suzukipilot »

I had a rubber boot for my carb and air cleaner that was hard as a rock. Impossible to fit.
Per a youtube video i soaked it a few days in 3 parts alcohol and 1 part wintergreen oil.
Soft and flexible again.
Heat gun also softens them, but for a very short time.
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