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Engine clatter, no oil? 87 SRV 540

2056 Views 16 Replies 5 Participants Last post by  rainbro
I bought this old sled seized, for about $50. Everythig seemed to have been in good condition except a small rip in the seat and it sat for 10 years untouched. I unseized the motor myself and got it running again with new hoses, plugs and belt. I didnt trust the oil injection at first so I filled the oil tank and ran mixed gas in it aswell. After noticing the oil level o down from running it and making sure it wasnt leaking I was sure i was buring the oil. So when I went low on gas I filled it up with regular gas and topped off the oil tank. Ran it for a while no problem. Came back a week later started it up and it was smoked like crazy so I was sure it was getting plenty of oil. Ran it for maybe 10 minutes started sounding weird and shut off. Started it back up with a clatter in the engine and it wont run on idle. So I dragged it back to the garage and havent touched it sence. I assume the oil injector failed and it wasnt getting oil, but the lines are full and not leaking and the oil level went down. Or perhaps somethig broke loose in the motor but I've ran it for 100miles already so why now? The engine clatters and wont idle and im afraid to run it in this state. Can someone confirm its an no oil situation? Or have I already damaged the motor? I am new to this snowmobile stuff. Is it possible the oil is too heavy that I put in it. Is it possible to fix this? Thanks I'll take all the help I can get.
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Your first step is a compression test if you have noise and it doesnt idle.
Sounds alot like my issue, kinda.I found out mine to be a stuck piston ring and it mared up the piston.So I'll be doing full top end rebuild.Mine also sat for numerous years and I also went through the samethings you did prior to trying and start it (fuel,oil lines. plugs, etc) I even poured some oil down the cylinders to prelube the rings and sleeves.
Yes, very similar. I'm still not sure if its a fixable issue and would like some more opinions on this.
Yes, very similar. I'm still not sure if its a fixable issue and would like some more opinions on this.

ANYTHING is fixable, it just depends on the cost.IF your hearing ANY noise from w/in the engine then SOMETHING is wrong. You "should" be able to tear down the head and jugs in under 30 mins & $30for gasket kit. Doing SO should allow you to find your problem. My $$ is on stuck ring OR bad wrist pin bearing. Your engine was ALREADY seized when you got it, so you must expect to have a problem DESPITE being able to "unseize" it:dunno:
Hope this Helps
Alright so would any of this have to do with anything I did prior to it?
Alright so would any of this have to do with anything I did prior to it?

From what you've mentioned it doesnt sound like you did anything WRONG. You said the motor was seized up when you got, yes?? What did you do to unseize it?? Do you know what was stuck??? The more info you can give us the better we can help;) AS previously mentioned, a compression test IS the first thing you should do and go from there.
But I already said I've driven it quite a while after it was unseized. To unseize it; I stared with pouring diesel oil mixturedown thy cylinders to free them, turns out it seeped right through so I took a breaker bar on the engine shaft after taking the pulley cord off and I worked it loose, I startes with a hammer on the bar then eventually got it to wiggle which turned into a full rotation in about a half hour and then worked it looser by turning it with a ratchet from then on. Then once loose enoug and after getting the carb unstuck I started it up with the mixed gas and all was well.
I need some feedback please.
When something sits for years, rust and gum accumulate. Rust probably formed on the rings causing them to sieze to the cylinder. Rust may have also formed in wrist pin and crank bearings scoring the pins. When a carb sits empty for years it also corrodes/gums clogging passages. This causes a lean condition thus not lubricating the engine properly. A full carb clean should have been performed before starting your engine. Check your plugs. Like I told you in the first post, check compression. This will determine if you have ring/cylinder damage and will tell you which side is the culprit
The carb WAS cleaned before running the engine, but like I said the only thing done to the engine was some oil poured down the cylinders.
whats the compression???
Update: Getting 40PSI per cylinder, pretty sure somethings wrong.
yep..something is wrong.

Should have at least 90 PSI each with compression test. Your idle problem is confirmed.

A breaker bar and diesel wreaks havoc on rings and mech parts, for future reference. Best is to get them loose with PB Blaster...then a healthy dose of oil while turning the engine over.

If she was seized for that long...your lucky you had it running in the first place. Top end rebuilds are relatively easy. Search this forum for a wealth of information. A good manual is your first step.
Alright then I have another motor from an 82 srv I could throw in until I get this one rebuilt. They are exactly the same except the 82 I'm pretty sure is board. I can transfer them over no problem but, the 82 has a different style carb then the 87 the 87 has a mikuni carb and the 82 has a different style carb. If I to bring the carbs with the motor there is so much extra hastle is it okay to switch them? 82 motor with mikuni carb?
If its been bored, It has probably been rejetted to accomodate for the extra displacement. Installing a carb without larger jets could be risky and you could end up with another meltdown. You could swap carbs, but check your spark plugs after a short run to ensure its not running too lean.
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