Printable Version | Subscribe | Add to Favourites
New Topic New Poll New Reply
Author: Subject: Bang, bang, bang again!
Guinness

posted on 28/5/06 at 05:14 PM Reply With Quote
Bang, bang, bang again!

Right, I'm getting pissed off with coming home on the back of a recovery truck.

Started the car, first time since Stoneleigh, ran it up to the petrol station, filled up with super unleaded, warmed it up and went out to play. About 20 miles further on pulling out of a 30 zone onto a national speed limit road I opened up the throttle and it started making horrible noises. Sounded like a big lump of something heavy hitting something metal.

Pulled over, killed the engine, took the bonnet off. Oil all over the shop, looks like it came out the breather on top of the gearbox. Started it up and it runs OK, apart from the horrible knocking sound and the oil / air spraying out the breather.

Jambojeef came out and had a look at it while we waited for the AA. Took the plugs out and they are all the same, a mid grey colour. Took the cam cover off and turned it over, everything looked OK, springs going up and down, all followers working ok.

The engine starts and runs OK, apart from this horrible noise. Any ideas? Anyone in the North East got a compression tester for a bike engine.

Cheers

Mike






View User's Profile View All Posts By User U2U Member
andyharding

posted on 28/5/06 at 05:25 PM Reply With Quote
Sounds bad. But you knew that.

Have you got a baffled sump?

Can you do a (sound) recording?





Are you a Mac user or a retard?

View User's Profile View All Posts By User U2U Member
ChrisGamlin

posted on 28/5/06 at 05:54 PM Reply With Quote
Whats the oil pressure like?






View User's Profile E-Mail User View All Posts By User U2U Member
ned

posted on 28/5/06 at 06:02 PM Reply With Quote
from your brief description if its worst case it sounds like big ends.

Ned.





beware, I've got yellow skin

View User's Profile E-Mail User Visit User's Homepage View All Posts By User U2U Member
Hellfire

posted on 28/5/06 at 06:12 PM Reply With Quote
Sounds like big ends... however, without a looky we can't tell

Does it only do it whilst moving? Could it be the prop by any chance. On this engine IIRC the engine is as it should be in the bike, right? The bike is prop driven, could it be this?

As this engine is pretty rare in a BEC finding a solution may be slightly more difficult than the rest of us with BEC's.






View User's Profile Visit User's Homepage View All Posts By User U2U Member
Bob C

posted on 28/5/06 at 06:22 PM Reply With Quote
Big ends don't suddenly go (in my limited experience...), I had a car that sounded sweet as a nut when cold but when it got hot & the oil thinned you got the bigend knocking.
I'd do a spanner check right down the transmission - a loose joint anywhere could sound like this.
be lucky!!!!
Bob
re read initial post - oil everywhere - that don't sound good

[Edited on 28/5/06 by Bob C]

View User's Profile Visit User's Homepage View All Posts By User U2U Member
Guinness

posted on 28/5/06 at 06:30 PM Reply With Quote
Thanks guys,

In order, yeah andy, sounded serious enough to make me stop! Sump is a GPZ900, straight swap for the standard.

Chris, not sure about oil pressure. Will re-fit sender and find out!

Ned, could be?!

Hellfire, nope, does it when stationary on tick over! Engine is wrong way round, longways, and normally chain driven.

Bob, I think I'm unlucky!

it's up on axle stands, so I can re-fit oil pressure sender, then if it's ok / non existant going to drop the sump and have a look.

Cheers

Mike






View User's Profile View All Posts By User U2U Member
G.Man

posted on 28/5/06 at 09:11 PM Reply With Quote
I have killed 2 car engines and when the big ends went, they went quickly...

Sounds fine on idle, but when you open throttle the knocking starts...

Big ends and mains are the first sign of oil starvation, as they require the most oil to stop the shells meeting the crank due to the load on them...

Sounds bad...







Opinions are like backsides..
Everyone has one, nobody wants to hear it and only other peoples stink!

View User's Profile View All Posts By User U2U Member
tks

posted on 28/5/06 at 09:45 PM Reply With Quote
Mhh

If it are the big ends wy would then the oil be everywhere??

also my opinion is that this is just no starvation!! not??

what would happen if the oil pressure was skyhigh..?? would it then spoil out of that place??

cant the head oil return channel/bore be blocked??

have no idea but the bigend and the oil everywhere cant see the conection also if the big end gets play, then the piston will hit the valve pretty much soon right?/

Tks





The above comments are always meant to be from the above persons perspective.

View User's Profile View All Posts By User U2U Member
G.Man

posted on 29/5/06 at 03:44 AM Reply With Quote
quote:
Originally posted by tks
If it are the big ends wy would then the oil be everywhere??

also my opinion is that this is just no starvation!! not??

what would happen if the oil pressure was skyhigh..?? would it then spoil out of that place??

cant the head oil return channel/bore be blocked??

have no idea but the bigend and the oil everywhere cant see the conection also if the big end gets play, then the piston will hit the valve pretty much soon right?/

Tks


Probably because the oil pump has blown the oil out rather than too the crank...

One could be cause and one effect..







Opinions are like backsides..
Everyone has one, nobody wants to hear it and only other peoples stink!

View User's Profile View All Posts By User U2U Member
russbost

posted on 29/5/06 at 02:35 PM Reply With Quote
Oil from the breather, it must be over pressuring the crankcase, sounds like a piston, having blown the oil out it would then run the bearings anyway.
NOTE:This user is registered as a LocostBuilders trader and may offer commercial services to other users
View User's Profile Visit User's Homepage View All Posts By User U2U Member
DarrenW

posted on 2/6/06 at 09:45 AM Reply With Quote
How are you getting on Mike? Has Yvonne fell out with you yet?

If you get the spare engine you can stash it at mine if you want until i have to move out. There is also an engine crane in my garage if you need it (hanging from beam type). I can make my garage available to you if you need it, its just a shame im a few miles away.

Let me know if i can help in any way.






View User's Profile E-Mail User View All Posts By User U2U Member

New Topic New Poll New Reply


go to top






Website design and SEO by Studio Montage

All content © 2001-16 LocostBuilders. Reproduction prohibited
Opinions expressed in public posts are those of the author and do not necessarily represent
the views of other users or any member of the LocostBuilders team.
Running XMB 1.8 Partagium [© 2002 XMB Group] on Apache under CentOS Linux
Founded, built and operated by ChrisW.