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Bad oil pump?

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Hey guys so last night i was installing my just repaired engine i did everything correctly oil and coolant on rads but when i was trying to start the bike she started but after 5 seconds of normal idle comes a weird rattle from engine. I immediately got the valve cover off and didn't found nothing except top end was dry with no oil. Can a bad oil pump be the cause?

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What exactly was 'just repaired' in that engine and, was it done by yourself or someone else?

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What exactly was 'just repaired' in that engine and, was it done by yourself or someone else?

It was done by my mechanic. Full engine rebuild repaired crank and installed carillo, new cylinder, new piston,new cam chain obviously all gaskets.

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I would not run the engine until you've discussed it with you mechanic then.

Edited by mlatour
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I would not run the engine until you've discussed it with you mechanic then.

First thing i did was to hit him up. He said it was a bad oil pump. I'll try to upload a video yo YT so you guys can see it.

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Was the engine repaired following a failure?

If so, the oil pump may have been full of debris, was it replaced?

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Generally speaking when you rebuild a top end, or even mess around with the valves. you coat everything (valve buckets, cams, cam journals, ETC.) with a moly compound (assembly lube) to prevent damage from a dry start or you would at the very least, pour some oil on the valve train before putting the valve cover on to help lubricate until the oil pump comes in and does it's job. If it is totally dry. I would seriously consider getting a new mechanic man. No lube on a valve train could cost you a whole engine.

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Generally speaking when you rebuild a top end, or even mess around with the valves. you coat everything (valve buckets, cams, cam journals, ETC.) with a moly compound (assembly lube) to prevent damage from a dry start or you would at the very least, pour some oil on the valve train before putting the valve cover on to help lubricate until the oil pump comes in and does it's job. If it is totally dry. I would seriously consider getting a new mechanic man. No lube on a valve train could cost you a whole engine.

It's true man. I just gave the man the oportunity cause i could do the assembly job.
Was the engine repaired following a failure?
If so, the oil pump may have been full of debris, was it replaced?

Yes crank main bearing failed.

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What year is the bike? I'd say you need to pull the engine back apart

08 I don't think i necessarily need to pull her apart again as i only started it twice for less than 5 seconds maybe as soon as i heard the rattle i cut her off. I'm replacing the oil pump tomorrow.

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Hope all goes well. Heads up there's 2 pumps. I believe the pump that feeds the top is on the clutch side of the cases

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Hope all goes well. Heads up there's 2 pumps. I believe the pump that feeds the top is on the clutch side of the cases

Thank's for the good wishes as soon as i install the new pumps i'll post back the come up.

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Man I hope everything is okay with your rebuilt motor. That would irritate me a bit.

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I'm still waiting on the pump's but i hope everything turns out fine as soon as i solve that.

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Its funny I was just looking at my wrench rabbit kit, bought the full rebuild for my 05 Rmz450..not that it needs it yet or is even close since it just had a Weisco Piston and Crank installed 14 hrs ago but I like to be prepared. I was thinking since I am in there I might as well replace all the important stuff like the oil pump/s..I am just curious, didn't you at least wonder about the oil pumps and in no way do I question your mechanical skills or anything like that, I am just curious. Are they a pretty tough part that SHOULD have been okay to roll with a new rebuilt engine because I don't know. I have learned a sh*t ton in the last month though about new 4 stroke MX motors. Very simple really.

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Its funny I was just looking at my wrench rabbit kit, bought the full rebuild for my 05 Rmz450..not that it needs it yet or is even close since it just had a Weisco Piston and Crank installed 14 hrs ago but I like to be prepared. I was thinking since I am in there I might as well replace all the important stuff like the oil pump/s..I am just curious, didn't you at least wonder about the oil pumps and in no way do I question your mechanical skills or anything like that, I am just curious. Are they a pretty tough part that SHOULD have been okay to roll with a new rebuilt engine because I don't know. I have learned a sh*t ton in the last month though about new 4 stroke MX motors. Very simple really.

It was totally my fault because i thought the oil pump was good. That could totally cost me an engine for that one
simple mistake. But thank god everything is okay. I was just lucky. But my friend everytime you rebuild an engine just replace the oil pumps for peace of mind.
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Ya I agree. Like I said I didn't mean any disrespect I know sometimes the interweb is easy to sound like an ass.

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