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Discussion Starter #1
I’m going to get a boost bottle but I’m not sure what the difference is between the small block and big block boost bottle. Is there a difference?
65074
 

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Big block is for the 800 and 700s, small block is for the 600s and 500s. Measure the distance between your two carbs where the boost bottle goes and you will know which one to get. Also look for used ones on eBay from SLP as they are a better boost bottle instead of those.
 

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Discussion Starter #3
Will do, can you buy new slp ones because I’ve looked all over and can’t find them?
 

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Nope you have to find them used. They pop up on eBay all the time. Just have to be quick about it though as when they do they usually go within 2-3 days regardless of price.
 

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There are some that take the small bock in that range as well dan, seen it myself from factory. Hence why I said to measure just to be safe. If new it should have measurements available on their website to measure between the 2 carbs if they don't then you should ask because of that possibility.
 

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Nope and they never will! Could have just been smart and done the 500s & 600s and some of the 440 XCRs as small block but that would mean using common sense. There are also at least 2 different cylinder numbers possibly 3 for those years. One set was better then the other when it comes to cracking at the base of the cylinder. We did a '98 XC 600 with a small block SLP bottle because no matter what the big block would just not fit right. Same thing ended up happening a few more times none of us could figure it out. Yet more often then not those years they used the big block one. Could be because of the manufacturing process being cheap or lazy or could be something else. We will never know.
 

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As I said measure the distance on the carbs where the boost bottle goes, that will tell you which boost bottle to get.
 

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If the engine has the water pump driven by a belt on the mag side, it's a big block. If the water pump is between the cylinders, it's a small block. The Polaris twins starting in 1997 were big blocks, they started with the 700, then the bb 600, then the 800. By 2001, the bb 600 was pretty much done, going to the small block instead.
 

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Yep pretty much what he said and measure the distance for the boost bottle. As I said it can happen as I described. I would have typed that out earlier but was out and about & feeling lazy,lol.
 

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John from Washington
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Saw this discussion and thought I'd chime in. I have a summit 800 that was difficult to start. My old Summit 670 has a primer and starts easily, so I looked for away to accommodate a primer on the Summit 800.

THe Summit 800 carbs don't accommodate the primer port and my stock 800 booster bottle was made of thin ABS plastic -- adding primer ports would have been risky.

SO, I custom made my own booster bottle that would accommodate the primer ports safely...now this ole sled starts with 2 pulls. Check out the pic.
 

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John from Washington
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The bottle was the easy part. The copper ends are "connection couplers" for 1/2 copper pipe and they fit the "receiving holes" in the boots perfectly. Amazing what you can do if you think outside the box.

The hard part was tapping into the fuel reserve and running the primer input line with a clean installation. The 'T-fitting" that came with the primer kit was too small in diameter, so I needed to make a custom (brass) one with parts from LOWES. The brass "T" added $15 to the project but all is forgotten when she starts on the 2nd pull!

I think the sled was designed to use the fuel-enrichment switch. I did not have time to tear into the carbs and I needed to get this thing running! When I have spare time (when pigs fly), I'll look at the enrichment circuit.
 
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