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-   -   Brand new rebuild - BLOWN? HELP! (https://www.rx7club.com/3rd-generation-specific-1993-2002-16/brand-new-rebuild-blown-help-622701/)

Wompa164 02-11-07 03:33 AM

Brand new rebuild - BLOWN? HELP!
 
I'm freaking out right now.

I have 750 miles on my brand new rebuild with 2 new housings. My motor has been running perfectly up until tonight. I've been babying the hell out of it - no higher than 3500 revs, no boost, generally being really careful with it.

My engine was running perfectly all night. I pulled into a parking lot (still running perfect) and went to dinner. When I came back and started my car, my engine was running rough - like it did when it blew last time. It ran a little rough, the idle was a little rough, and my vacuum was a little lower than normal (nothing terrible).

What the hell is going on? I already checked my MAP sensor and the vacuum line - that's fine. I tried quickly reseating my sparkplug wires, I'll check them again tomorrow though.

Do you guys have any ideas? I don't know how this engine would have blown already. I haven't run any boost, I've been babying the hell out of it, and suddenly it just started acting funky.

Please help - I'm worrying myself sick here.

R-R-Rx7 02-11-07 05:52 AM

go for a compression test

this will answer ur questions

Con

BlueTII 02-11-07 06:19 AM

Your plugs could just be carboned up from taking it easy during the break in. I depends on how you have it tuned and if you are running premix, etc etc.

Wompa164 02-11-07 06:29 AM

That's what I thought. They're also the same plugs I was running since before my rebuild.

tiger18 02-11-07 06:31 AM

I bet you its just flooded,,, do a full unflood and clean and dry the plugs.

BlueTII 02-11-07 07:39 AM


Originally Posted by Wompa164
That's what I thought. They're also the same plugs I was running since before my rebuild.

Ok then, just change your plugs out, then report back if the problem continues. Depending on what was used to assemble the engine, there is a lot of crap that also burns off, which can also foul the plugs (hylomar, assembly lube, vaseline etc)

ArmitageGVR4 02-11-07 08:29 AM

edit: I need to learn to read.

DaleClark 02-11-07 09:51 AM

Yeah, check with the easy things first. I HIGHLY doubt your motor's blown - it hasn't seen any real load yet, and it sounds like you did things right with that motor. This is also part of the reason for breaking in a motor - bugs will crop up from the installation that need to be sorted out.

Dale

GoodfellaFD3S 02-11-07 10:29 AM

I've never seen a fresh motor exhibit symptoms like that, although I always install new spark plugs on all my builds. Is the needle on your boost gauge 'ticking' back and forth at idle? I hope the motor is fine, based on how you've been driving it I can't imagine it's blown.

1QWIK7 02-11-07 11:54 AM


Originally Posted by BlueTII
Your plugs could just be carboned up from taking it easy during the break in. I depends on how you have it tuned and if you are running premix, etc etc.


Agreed.

I remember pulling off some 7 month old plugs that were carbon'd the hell up because of when the car was mostly down, i made alot of short trips, no WOT runs, nothing, alot of warming up the car and idling. I cant believe how bad the plugs got in that short period of time.

Speaking of that, i need to change my plugs again.

mono4lamar 02-11-07 02:05 PM

as rich said... if your needle at low idle flickers that means you have a seal/seals problem. i would go get some new plugs and as you change do a quick compression check... what size seals do you have sometimes new 3mm's get sticky i had this happen on my new motor. i wouldn't worry my motor some nights just ran shitty as it was being broken in. get some new plugs and a compression check and report back.

AgentSpeed 02-11-07 02:21 PM

Where's the pics of this new motor and turbo setup? Like most have said, I think you're fine, just put in some new plugs.

Wompa164 02-11-07 07:44 PM

Put 4 new plugs in - didn't change a thing.

Guess I'll get a compression test tomorrow.

Sigh.

mono4lamar 02-11-07 08:18 PM

who did the build? any porting? what seals? whats your lowest vac reading and what rpm is that at?

Wompa164 02-11-07 08:24 PM

Don Marvel of Marvelspeed.

Stock 2mm OEM seals with new OEM seals for everything.

GoodfellaFD3S 02-11-07 08:26 PM


Originally Posted by Wompa164
Don Marvel of Marvelspeed.

Stock 2mm OEM seals with new OEM seals for everything.

You're not answering a lot of the questions asked. Is your needle on your boost gauge 'ticking' back and forth slightly at idle? What is your vacuum at what idle rpm? Providing more info would help us to help you better :)

Wompa164 02-12-07 01:07 AM

The needle is pretty constant. It doesn't flicker or anything, but it does go up and down as the idle changes (which is to be expected).

My vacuum is about 15 inches at 1000rpms.

I don't really know what to think at this point. Maybe a stuck apex seal?

Buzzardsluck 02-12-07 01:49 AM

Ported motor? Is that why your idle is at 1000rpm? Is your standalone a PFC?

Hope its a simple fix and if need be your engine builder helps you out to fix the problem.

spandy 02-12-07 02:44 AM

Shouldn't there be some type of warranty if something was wrong?

GregFD3S 02-12-07 03:24 AM

did youhttp://img511.imageshack.us/img511/1...oncheckrh5.gifyet?

GoodfellaFD3S 02-12-07 08:26 AM


Originally Posted by Wompa164
The needle is pretty constant. It doesn't flicker or anything, but it does go up and down as the idle changes (which is to be expected).

My vacuum is about 15 inches at 1000rpms.

I don't really know what to think at this point. Maybe a stuck apex seal?

I would bring it back to marvelspeed and see what they can tell you. Based on all of that information above, the motor doesn't sound blown :)

mirabile 02-12-07 09:02 AM

I agree with Rich. Dont listen to him that much though, he doesnt come to rotor meets on sundays. ;)

GoodfellaFD3S 02-12-07 10:44 AM


Originally Posted by mirabile
I agree with Rich. Dont listen to him that much though, he doesnt come to rotor meets on sundays. ;)

Sorry, my Eskimo suit was at the dry cleaners :D

Wompa164 02-12-07 09:50 PM

Hey guys,

I'm hoping it might be a stuck injector (or injectors). The car has 104,xxx miles and I'm not sure the primary injectors have ever been cleaned or replaced, so we'll see in a few days.

The car also starts perfectly, warm or cold. I noticed the threads of my plugs on one of my rotors were thinly coated in oil when I pulled them out. Could that be because the OMP is injecting oil which is not getting combusted (no fuel) and just sloshing around inside the housing?

Whatcha guys think?

car hugger 02-12-07 10:18 PM

Check all your piping and make sure everythings secure and set right. My crossover pipe would come loose and my idle would go rough, boost gauge would flicker.


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