Clatter, clatter, knock, knock

[zedhex]

My 944 turbo just gave me its Christmas/New Year present. I had put it on sorn for the winter months, and yesterday I decided to run the engine to get some oil around it. It started up just fine, but with a loud clatter. I didn't think much of it, as it quieted down after a couple of seconds. This morning I wanted to move it out of the garage to work on another car. I started the engine, and this time it started making a serious knocking noise - and it did not quiet down. Not good - a solid clonking noise from deep within the engine. It sounds like a bearing has gone on the bottom end somewhere, and there is also a loud clatter from the cam area at half engine speed. It sounds to me that the start-up from cold after standing for two months has damaged a bearing.

Not happy at all...

I think I need to pull the engine and strip it - I have done plenty of engines before, but never a 944. What kind of expense am I looking at? Are all the parts available?

[robmal]

The solid clonking doesn't sound great - but the chatter from the top end is something which has unnerved most of us who do not use their cars as a daily driver. If I leave my 944S2 for a month then I expect the oil to have drained down and for there to be a bit of top end chatter for a minute or so, so don't worry about that particular noise.

If you do have a bottom end problem then I am sure someone here will talk you through the procedure for diagnosis - GOOD LUCK!

[nicksonmsport]

If once you strip down and find issues I have many good turbo engine internals here. Crank, pistons and rarst forged rods, as well as a good turbo block with very good bores. Complete heads and cam towers too.

All the rebuild bits such as bearings/gaskets etc are all available and not too expensive in std size. Oversize will be pricey so best to source good crank if required rather than grind etc.

Good luck with your findings!

Give me a shout if there is anything you require.

Regards

[nicksonmsport]

Happy to point you in right direction for rebuild parts too etc once you find out the problem

Regards

[zedhex]

Thanks for the replies. I will taking the motor out some time in the next few weeks (assuming I can find the time). Nick: I will be in touch as soon as I know exactly what has happened.

I am now regretting buying a 'cheap' 944 - in the Porsche world, things are cheap only for a good reason (I guess I may have been spoiled by my Soarer: cheap, fast + reliable does happen occasionally).

[nicksonmsport]

lol, i had a soarer too! awesome engines! i have various customers running 6/700bhp on 1jz and 2jz engines that have never even been opened up, with perfect reliability!

tbh those engines are an exception to the rule!

have faith, im sure you will be able to sort your engine without spending silly money

and 44 turbos are worth a lot more than a soarer will ever be, so spending a bit extra to keep them sweet isnt as bad as it could be

let us know what you find, be interested to see what has caused the failure

regards
nick

[zedhex]

Latest news - I am a complete idiot!

I was all set to strip down the engine, so I started her up, drove around the yard, into my garage and started checking the engine engine over with a stethoscope to see if I could identify exactly where the problem was. The noises were mostly located toward the back of the cambox, but the bottom end was completely quiet (odd cos I remember it was knocking last week). But, after about 5 minutes of running, to my astonishment, the noises slowly went away!??? very strange - is this normal? Do 944s really make that much noise after standing for a while? The noises were really bad (I could hear it from within the car), but now there is no noise at all. I have had engines clatter from cold before, but that would normally go away after a few seconds on most cars. On my 944, this was after 10 minutes of running - how could oil take that long to get around an engine? Maybe the hydraulic tappets not filling properly? But its quiet now, just the ticking of the injectors, no knocks, no clatter.

Good news all round, but I am still a bit suspicious - from now on, I will be starting the engine every week just to get the oil flowing. I don't think that running dry after a long sleep will help engine longevity at all.

[Waylander]

that can be quite disturbing, when I had my 968 up on stands for 8 weeks, (mainly waiting for parts) when I restarted it, it took the best part of 15mins for the tappets to fully shut up.

they make a surprising amount of noise.

[edh]

Sounds normal...

Empty hydraulic tappets make the most awful racket - and take much longer than you might expect to refill. I don't think it does any damage though as far as I am aware - no need to start the car every week just to keep them filled.

[PSH]

Hi

I was reading through the posts thinking to myself that I doubt it's a bearing and then see you have discovered that things aren't as bad as first thought, which is good news.. 944's don't really like standing around for too long, a noisy engine start can be a number of things with the most common none terminal being stuck tappets or drained oil, both result in top engine noise. Drained oil usually clears within a few seconds once the pump has pressurised the system, keep an eye on the oil pressure gauge and that the oil pressure is good once the noise has gone, pressure on a cold engine should be 5 bar. Stuck tappets can take longer, many minutes in fact or in worse cases not clear at all until they are treated or stripped down, they rarely need replacing, very rarely and usually only due to the result of other damage occurring elsewhere in the engine. In regards to a failed bearing you would notice a drop in oil pressure so always know your car, read the gauges as if a plane, they are important. Going back to the drained oil scenario, only use genuine oil filters and change both these and the oil regularly, you'll find that the car will be able to stand longer before the oil drains down.

Regards

Pete

[flt505]

If anyone remembers watching Kelly's Heroes, the Panzers (designed by Herr Porsche) had to restart their engines on a regular basis to keep the oil warm and battle ready. On the Brit side of things, the WW2 RAF Hawker Typhoon also had to do the same, often with duvets covering their huge engines, just before an operation...

There is a moral here: If you have a Panzer, keep the engine ready and if you are a Brit, just use a duvet...

Dave
CT

[Waylander]

Lol Dave, duvet day sounds fantastic

[Pink piggy]

If anyone remembers watching Kelly's Heroes, the Panzers (designed by Herr Porsche) had to restart their engines on a regular basis to keep the oil warm and battle ready. On the Brit side of things, the WW2 RAF Hawker Typhoon also had to do the same, often with duvets covering their huge engines, just before an operation...

There is a moral here: If you have a Panzer, keep the engine ready and if you are a Brit, just use a duvet...

Dave
CT

Ha I once read a book called 'Stuka Pilot' written by Hans Rudel and he fought on the Russian front and they would have fires burning under their aircraft to stop the engines from freezing up!
However I am not sure starting fires under our cars will be a good way to go

[Largie]

Lighting fires under JCBs, trucks and other construction plant was very common 20 or so years ago to thaw out frozen/freezing diesel fuel supply pipes. They then started putting additives into diesel fuel to stop it freezing.

David

[mr brightside]

I've got this issue, it's only from cold and a bit embarrasing sometimes tbh.

Why does it happen? Is there a NRV in the gallery to the top end that fails, or is it symptomatic of pump wear?