Cerbera "nipped up" after dyno run

[MackemPete]

Hi,
I did a dyno run on Saturday to check to see if my car was still putting out a healthy number. Immediately after the run the dyno operator turned it off and it wouldn't restart. The dyno operator seemed to think it had nipped up, believe this is where the crank welds itself to the bearings. I left it for 10 mins and it started fine. So I'm putting it down to the usual hot start issue.

Anyone know how I can easily rule out the nipped up diagnosis? Drop sump and check for metal?

[FarmyardPants]

I would suggest the dyno operator was talking bks and your car is fine.

More to the point, what power did it make?

[MackemPete]

Disappointingly only 370. Has previously made 420ish. However it's only 250 miles out of its winter layup. Could probably do with plugs and HT leads too.

So is the bks diagnosis based on anything in particular?

[TheRainMaker]

"nipped up" that's a first

Does it "nip up" on the road?

[MackemPete]

It did the same when it went for its MOT. Done a few hundred miles since then and still has good oil pressure and bottom end isn't knocking itself to bits.

By all accounts the company with the dyno have a good rep, certainly they know more about cars than me, so I don't like to ignore their comments out of hand. However car is still driving fine and showing no signs of impending death.

[TheRainMaker]

It's more likely to be the starter on its last legs imo

Never heard of a cerb that has nipped up.

[Boosted LS1]

If the engine had 'nipped up' you'd know about it because that would be a partial seizure which is unlikely to remedy itself.

[gruffalo]

TheRainMaker said:

It's more likely to be the starter on its last legs imo

Never heard of a cerb that has nipped up.

Most likely this due to the heat build up caused by being run flat out under load when stationary and no air flow.

[MackemPete]

Cheers folks. I'll go back to worrying about the things I know need fixing

[Jhonno]

Boosted LS1 said:

If the engine had 'nipped up' you'd know about it because that would be a partial seizure which is unlikely to remedy itself.

This.

[spitfire4v8]

He would have been talking more about pistons in bore than crank, but any which way you would have known if that had happened! Just sounds like starter motor as others have said.
Is this the engine that made 420 on my dyno and 417 at SRR ? if so it sounds like you do have other issues going on though ..

[hillclimbmanic]

Jhonno said:

Boosted LS1 said:

If the engine had 'nipped up' you'd know about it because that would be a partial seizure which is unlikely to remedy itself.

This.

Exactly...

[andy43]

Having shagged the bearings on an old Mazda, that started knocking and got worse.
After stopping for five minutes it started quieter and smoother than when I'd stopped it presumably as it had cooled so I'm thinking the concept of locking solid after doing a bit of full revs work then ticking over like a pussy cat is flawed! Tvrs do make their own rules though

Edited by andy43 on Wednesday 30th March 09:26

[stlol]

Bad move running it flat out on a dyno then turning off immediately, massive heat soak, are you sure they know what they are doing?

[wiggycerb]

I would of thought it was heat soak affecting the starter solenoid.

[MackemPete]

spitfire4v8 said:

He would have been talking more about pistons in bore than crank, but any which way you would have known if that had happened! Just sounds like starter motor as others have said.
Is this the engine that made 420 on my dyno and 417 at SRR ? if so it sounds like you do have other issues going on though ..

That's the one. Came in for short induction, remap and shocks and dampers. Only the 417 was at a local firm who had the same rolling road as you. Good memory as this was a good few years back.

Undoubtedly I have something amiss. Going to get booked in for a 12k service and replace the HT leads as they look past their best. I'll explain the situation to the specialist doing the service and see if they can find my missing horses!