GT500 OIL PUMP SETTINGS

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2smoker_384
Still in the Driveway
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Joined: Tue Jun 18, 2013 4:58 am
Country: united kingdom
Suzuki 2-Strokes: GT500

GT500 OIL PUMP SETTINGS

Post by 2smoker_384 »

Hi, in trying to recapture my youth, I've been and bought a 1977 GT500. I had the GT550 back in my teens and my mate had the GT500. I always loved the look and sound of it. They are just perfectly proportioned. I find myself in the garage with a cup of tea, just sitting and looking at it. Anyway, I need some advice on the oil pump settings please. The handbook says the line on the pump arm should line up with the mark on the pump body (small protruding round part?) near the pump base, when the throttle is wide open. Also, when the throttle is closed, another lower mark on the arm, should line up with the same mark. On my pump arm, the lower mark appears to be two small dots, punch marks about 3mm apart. If I adjust the cable so the higher mark lines up at full throttle, with the throttle closed, the cable is really slack. However, if I adjust the cable so the lower pump arm marks line up at closed throttle (i'm assuming midway between the two small punch marks) when the throttle is wide open, the pump arm is way past the full throttle mark. Is the pump still working, providing oil to the engine if the cable is really slack. I'm just a little confused. I do have other issues with the bike which I will post later but for the moment, I'd like to get this sorted. Thanks very much for taking the time to read my message. Phil :up:
titan performance
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Suzuki 2-Strokes: TS100, T200, GT250, T500, GT500, GT550, GT750, GS750
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Re: GT500 OIL PUMP SETTINGS

Post by titan performance »

I must admit that after owning many 500's continuously since 1977, I have never worried about where the oil pump arm rests at closed throttle. I have always set my pumps, as you have done, at full throttle. I should add, that after 10's of 1000's of miles on 500's, I have never seized one.
The oil pump is driven off the gearbox, so it is operating when the engine is running, and will only stop when the clutch is pulled isolating the box from the motor.
Keeping old 2 strokes alive !
Craig380
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Re: GT500 OIL PUMP SETTINGS

Post by Craig380 »

Hi and welcome. What Titan said: the pump's operating arm increases the amount of oil as the throttle is opened, but the pump still delivers oil even when the throttle is closed and the pump's arm is at it's resting position.
1976 GT380 - wounded by me, and sold on
2006 SV650S - killed by a patch of diesel and a kerb in Feb 2019
2017 SV650 AL7 - naked and unashamed
2smoker_384
Still in the Driveway
Posts: 3
Joined: Tue Jun 18, 2013 4:58 am
Country: united kingdom
Suzuki 2-Strokes: GT500

Re: GT500 OIL PUMP SETTINGS

Post by 2smoker_384 »

Thankyou very much for your quick replies. I'll do as suggested and set to throttle wide open. It has put my mind at rest. Nothing like asking the right people for advice. I'm going to fit the oil feed lines so I'm going to start with replacing the union bolt washers. I see they are plastic, would you suggest replacing like for like or sourcing some copper ones. Also, one of the union bolts I have in the box, is slightly longer than the rest. Any idea why or where this one should go. Many thanks for your help. Phil :clap:
Bloop2
To the on ramp
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Joined: Tue Jan 22, 2013 3:40 pm
Country: Ontario, Canada
Suzuki 2-Strokes: B100P,T200, 68,70,74 T500,GS650G DL1000

Re: GT500 OIL PUMP SETTINGS

Post by Bloop2 »

2smoker_384 wrote:I'm going to fit the oil feed lines so I'm going to start with replacing the union bolt washers. I see they are plastic, would you suggest replacing like for like or sourcing some copper ones.
The plastic ones should be replaced unless you want to have leaks, Suzuki still sells an updated version, an aluminum crush washer.

Most people have switched over to Stat-O-Seal washers, available at McMaster -Carr:

http://www.mcmaster.com/#stat-o-seal-washers/=n8yzf9" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;

The right size would be the 6mm.

Forgot you're in the UK, not sure if you can source them over there or get something similar, I know that McMaster Carr doesn't ship outside the US, learned that one a long time ago.

Fred
68 B100P x2
68 T500 Cobra x3
69 T500
70 T500 x2
74 T500
76 GT500
76 GT185 x2
81 GS650G x2
04 DL1000
2smoker_384
Still in the Driveway
Posts: 3
Joined: Tue Jun 18, 2013 4:58 am
Country: united kingdom
Suzuki 2-Strokes: GT500

Re: GT500 OIL PUMP SETTINGS

Post by 2smoker_384 »

Cheers Fred. I'll try and source some on the internet. Failing that, there is a large autojumble taking place towards the end of July. It's a fair distance from me but might be worth the trip. All the best, Phil
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