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  #1  
Old 11-11-2010, 11:46 AM
Jonota Jonota is offline
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Default Crossfire 150R Issues

Hey guys! New to forum, looking for some help, eventually hope to give some myself.

I've been researching buggies for several weeks, and this issue about 2 weeks itself. I purchased a Crossfire 150R from a local guy. He drove about 2 hours to deliver it to me. Initially, after a jump, it fired right up and idled fine. It backup up approximately 10ft just fine, went into forward and took off apparently normal. After about 30 yards it shut down completely and hasn't had any "fire" since then.

Immediately we spent about 2 hours going through the cart, as I was reluctant to purchase. Eventually, I offered him less expecting a clogged carb jet. We were getting spark, sounds of compression, but no fuel to the plug. After tearing the carb down and blowing it all out, I get fuel to the plug now, but still no fire whatsoever.

After research, generally the advice seemed to be valves/valve timing. I have verified that w/ the line to the left of the "T" on the flywheel aligned to the large mark on the engine casing, the 2 small holes on the cam gear are level w/the head, and the big hole is up. I also adjusted the valves to .003" in this condition (initially, the exhaust valves had a good INCH of clearance!). Still no fire. I have a compression gauge, but don't have the adapter to fit the small hole. If I put my finger on the hole I have to apply a decent amount of pressure to keep it from blowing past my fingers... I have read 130psi... so I'm not sure if this is enough.

The only "glaring" deficiency I can find at this point is that the enrichment/auto choke does not have an o-ring installed in it. I don't think that this would completely prevent it from running. I have not recently reverified that I have spark, so I may have lost that in process. I sincerely hope I didn't just buy a cart when it gave up the ghost on the engine. It is supposedly a bored/stroked Howhit 175cc+ (haven't done any verification, but have receipts).

Any suggestions? Directions? I tried **********.com and haven't had any responses so far... I'm at a loss besides pulling the entire engine assembly and tearing it all the way down. I'm itching to go out with the boys, as I've bought a new 150cc and 110cc for them to ride in. I've gotta say I'm very impressed with the stock 150cc, so I'm curious to see just how impressive this modified engine will be.

Thanks in advance for any replies!

Jon
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  #2  
Old 11-11-2010, 01:41 PM
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metalstudman1 metalstudman1 is offline
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I have that compression gauge too!!! The fact that it ran a short period of time is usually a symptom of the enrichment valve not working right.Test it -apply power to it and see if the brass end extends after a few minutes or you can just disconnect the plug and pump the gas rapidly to see if it starts or floods it.
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Old 11-11-2010, 02:13 PM
Jonota Jonota is offline
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I've been trying various starting methods. I have 3 different enrichment valves (came w/ a BIG box of extra parts)... but no o-ring. Various amounts of throttle while trying to start it just changes how wet the plug is when I pull it now.

Next time I'm at a hardware store I gotta see if I can find an adapter to check compression. Looking around, I'm very afraid I have a cracked piston or ruined rings. I did put a tad bit of oil in the cylinder to see if it was washed rings and try to up the compression, but it made no difference.

Jon
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Old 08-28-2013, 01:27 AM
Jonota Jonota is offline
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Resurrecting the old thread, but mostly for closure for people searching for issues.

I did indeed discover that I bought a buggy after watching the engine blow. I pulled the head to discover a significant portion of the piston missing, as well as a bent intake valve. Ended up purchasing a full BBK kit w/ cam and rebuilding the entire thing (including crank, as I ended up wallowing out the keyway).

The biggest part of the story is the seller. He swore to me he drove it in the condition it was in plenty of times before. After all that I have been through there is NO WAY that is the truth. The engine had ALL of the cooling shrouds removed - I found this out after almost burning up the brand new BBK install (and it was likely the cause of the dead piston). Also, the gearing had a 26tooth sprocket on the axle, and a 34tooth sprocket on the OUTPUT SHAFT (yeah, the one that is normally 13-16 tooth). So the gearing was incredibly tall. Until I figured out that was bad I couldn't get it over about 12mph or so.

But happy ending is that the cart has been running beautifully for some time now. Biggest issue I have no is a small drop of oil I'm getting from the drain plug!
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Old 08-28-2013, 01:29 PM
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Did you change your output sprocket to a much smaller size? 34terth is unheard of. And if you did you'll have to go up on your axle sprocket to about 39 teeth approx.. on your frain plug you may need a new rubber washer..." don't over tighten it."
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Old 08-28-2013, 06:08 PM
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did you ever get you a compression tester. I bought one from Harbor Freight lately and it had the size of adapter with it to fit the Howhiit. It came with 4 adapters and was regular price of $30 but they had it on sale for 19.95 and it worked great. even came with a nice case.
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Old 08-29-2013, 04:05 AM
Jonota Jonota is offline
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Quote:
Originally Posted by Miamieddie View Post
Did you change your output sprocket to a much smaller size? 34terth is unheard of. And if you did you'll have to go up on your axle sprocket to about 39 teeth approx.. on your frain plug you may need a new rubber washer..." don't over tighten it."
I ended up getting a 13tooth output sprocket to drive it. It currently has 23" ITP mudlites on the back, and with the 13/34 I think it pulls just fine for the time being (10.5 sliders/yellow spring). I might go up in the future but for now just happy to play around with it (it has been solid for quite some time now)

I will be getting the rubber/nylon washer.... I'm just glad that's my BIGGEST issue!

I have not gotten a new compression tester, particularly with these engines now I'm a fair enough hand I can have them out of the cart and fairly torn down within half an hour so I won't bother.
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Old 08-29-2013, 10:42 AM
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If she's pulling and riding fine and satisfied you don't need a compression test. Trust me you'll know if she has no compression real quick... enjoy be safe.
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Old 08-30-2013, 05:59 PM
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Geez, I just love a story with a happy ending!!! good job!
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Old 09-01-2013, 01:34 PM
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Some say you don't need a compression tester, but it saves you a lot of time checking this and that. I mean it only takes less than 5 minutes to hook it up compared to the time you spend climbing all over the engine looking for other problems when that's not the problem. Best $20 I ever spent, i think.
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Old 09-01-2013, 01:38 PM
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zman007007 zman007007 is offline
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you could prob. have saved even more money if you had carried a comp. tester with you and showed him it was blown. just saying. It lets you know basically what the inside of the engine is like.
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Old 09-01-2013, 01:45 PM
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I have to agree with zman. A compression tester is ur best friend.
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Old 09-01-2013, 02:47 PM
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the H/F item number is 66216 if that helps anyone. price on it is $20.99
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