MR2 Roadster Owners Club

The Workshop => Performance Related => Topic started by: Dudi on November 20, 2018, 13:06

Title: 2zz bottom end knocking
Post by: Dudi on November 20, 2018, 13:06
So at Anglesey yesterday the car developed a bottom end knock.

Looking for some inspiration as to where to go from here. We aren't sure why it happened, aftermarket oil temp and pressure gauge showed nothing abnormal, Elise parts sump and millers Ester oil.

I'm thinking either a reconditioned 2zz or a built 2zz as I've recently had a new gearbox etc installed.

K20 is an outside bet.

Title: Re: 2zz bottom end knocking
Post by: Alex Knight on November 22, 2018, 11:51
What weight oil were you using?

Which tyres?

If it were me, I'd be looking for a cheap Corolla/Celica T-Sport and just do a quick swap. It's pretty easy.
Title: Re: 2zz bottom end knocking
Post by: Dudi on November 24, 2018, 13:40
5w-40 Millers CFS and AD08R's

I'm thinking oil cooler at a minimum but any other upgrades I can make internally to minimise possible failures?

Updated oil pump?

Upgraded pistons and or rods?

Title: Re: 2zz bottom end knocking
Post by: inside on November 24, 2018, 20:05
If it is any consolation I had the same thing happen to me a month ago at the local track. Well maintained engine, 1zz sump with lowered pickup, oil cooler with gauges... Oil pump must have starved because all bearings were shot especially one.  :-\

From my understanding oil pump couldn't be the cause for this, just the sump and pickup.

I definitely need new engine, probably with moroso sump or similar...
Title: Re: 2zz bottom end knocking
Post by: inside on November 24, 2018, 20:08
Hmm, I've just saw you had eliseparts sump... is that one like a modified 1zz sump?
Title: Re: 2zz bottom end knocking
Post by: Dudi on November 25, 2018, 09:58
Quote from: inside on November 24, 2018, 20:08
Hmm, I've just saw you had eliseparts sump... is that one like a modified 1zz sump?

It's a better fitting version of the Moroso sump.

Bit worrying to hear yours lurched itself with an oil cooler as well.
Title: Re: 2zz bottom end knocking
Post by: inside on November 25, 2018, 16:30
This one? https://www.eliseparts.com/products/show/94/990/baffled-sump-toyota/

That's a shame it happened even with this sump installed.

So what's your plan then for new engine?

I'm thinking: new used engine, new sump, perhaps racing tri-metal conrod bearings, oil cooler.
Title: Re: 2zz bottom end knocking
Post by: Dudi on November 25, 2018, 18:27
I'm not sure what to do to be honest. It was a track used engine before I bought it so plenty of hard miles so part of me is tempted to get a fully reconditioned stock engine to see what it does.

The man maths part says while I'm having an engine it'd be good to have a new build with cams, better valves for a higher rev limit as well as build the bottom end for performance + reliability.

I won't be able to drive it anytime soon as I've ruptured my achilles so it gives me plenty of time to do research. I was really tempted by a K20 swap and actually told Andy at Bonsai that if my engine did go I'd be up for one but he has closed shop so that options maybe out the running unless someone else can recommend a garage that does the K20 swap?
Title: Re: 2zz bottom end knocking
Post by: james_ly on November 26, 2018, 15:44
Lots of us would cheer you on to be the guinea pig K20 swap... it does seem hard to find information on it.
Title: Re: 2zz bottom end knocking
Post by: Alex Knight on November 26, 2018, 16:00
Quote from: Dudi on November 24, 2018, 13:40
5w-40 Millers CFS and AD08R's

I'm thinking oil cooler at a minimum but any other upgrades I can make internally to minimise possible failures?

Updated oil pump?

Upgraded pistons and or rods?

Could be totally coincidental, however I've always used a minimum of ~W50 (Hot) engine oil for track (and road) work. Currently using Gulf Competition 15W50: https://www.opieoils.co.uk/p-60123-gulf-competition-15w-50-racing-ester-fully-synthetic-engine-oil.aspx

Totally depends on how you drive the car, but I've always wanted that bit of extra hot viscosity protection that a thicker oil provides on track.
Sure, you sacrifice a bit of top end power, fuel consumption and cold start protection, but it's worth the extra piece of mind for me.
Title: Re: 2zz bottom end knocking
Post by: Dudi on November 28, 2018, 14:55
I will definitely try a more viscous grade next. Both my others cars run 10W-60 so I understand the benefit.
Title: Re: 2zz bottom end knocking
Post by: m1tch on November 29, 2018, 13:39
Did you over-rev the stock oil pump?
Title: Re: 2zz bottom end knocking
Post by: inside on November 29, 2018, 14:36
Quote from: m1tch on November 29, 2018, 13:39
Did you over-rev the stock oil pump?

How would that work? As far as I understand the subject, over-reving oil pump (engine) would shatter the oil pump - and not silently decrease oil supply and cause bearings to fail...?
Title: Re: 2zz bottom end knocking
Post by: Dudi on November 29, 2018, 19:58
Quote from: m1tch on November 29, 2018, 13:39
Did you over-rev the stock oil pump?

It did cross my mind but it was fine after the last track day and certainly no over revs on the most recent one where the engine failed.

I'm not sure if I'll get the engine taken apart to check how it failed.
Title: Re: 2zz bottom end knocking
Post by: shnazzle on November 29, 2018, 21:57
Quote from: Dudi on November 29, 2018, 19:58
Quote from: m1tch on November 29, 2018, 13:39
Did you over-rev the stock oil pump?

It did cross my mind but it was fine after the last track day and certainly no over revs on the most recent one where the engine failed.

I'm not sure if I'll get the engine taken apart to check how it failed.
Excessive heat? Oil temps could have been a bit on the high side,causing the bearings to finally wear beyond repair.
Wouldn't be the first track 2zz that needed an oil cooler installed.
Pump can work fine, sump great but if it gets too hot the pressure reduces a lot and thin too much.
Above advice using a higher weight is definitely a good idea and would prevent it happening again.
Oil cooler with thermostatic valve to let it warm quickly
Title: Re: 2zz bottom end knocking
Post by: Carolyn on November 30, 2018, 18:42
I've been watching this thread with interest.

If it were my engine, I'd be dropping the pan and having a look at the rod bearings. 

If it's only a track-day car, I'd be tempted to clean any white-metal build-up off the crank, give it some new shells and check the clearances with plasti-gauge and then see if I can get more useful life out of it.
Title: Re: 2zz bottom end knocking
Post by: inside on November 30, 2018, 19:20
Quote from: Carolyn on November 30, 2018, 18:42
I've been watching this thread with interest.

If it were my engine, I'd be dropping the pan and having a look at the rod bearings. 

If it's only a track-day car, I'd be tempted to clean any white-metal build-up off the crank, give it some new shells and check the clearances with plasti-gauge and then see if I can get more useful life out of it.

Exactly what I did with my engine, however it wasn't successful - knock returned in 100 miles. "New" engine now on the way.