TIPEC

The TIPEC Forum
It is currently Thu Nov 15, 2018 11:47 am
Asset Trust


All times are UTC [ DST ]




Post new topic Reply to topic  [ 45 posts ]  Go to page 1, 2, 3  Next
Author Message
 Post subject: 944 2.5 big end shells
PostPosted: Mon Jul 16, 2018 12:58 pm 
Offline

Joined: Fri Nov 23, 2012 10:41 pm
Posts: 804
Location: Lincs
TIPEC membership: 6726
We'll its been a long time since i made a regular contribution on here. I've been focusing on my VW classic as the Porsche has been running very well. That is until of late, I've had oil pressure issues. It seems to flick up and Down between 3-5 bar when cursing along constant throttle ect.

There is also a loss of pressure around 0.5bar when i put my foot down.

I drained the oil and there were a couple of tiny metallic looking bits, so i figured id take the sump off and check. 1 rod bearing is showing a flec of copper. The rest aren't bad at all.

I'm at a bit of a loose ends, the bearings don't seem bad enough to cause the huge oil pressure fluctuations I've been seeing. I've changed the pressure sender, cleaned the gauge connection and had the oprv out and its moving freely.

Given all this i was going to put a set of rod bearings in and see what happens, £60ish quid a set its worth the chance given i cant afford a full engine rebuild right now and i also don't have the time.

Then i noticed the 0.25 stamp on a shell, it seems very hard to get oversize big end shells and i rang Porsche today who quoted £221+vat. Which is mental! Why are they 5 times the price??? Surely as the cars age more and more till need the oversize?

So I'm looking for advice/support/solutions/reasonably priced parts.

Any help is appreciated.

Also, how are we all getting on with those top mounts? I've out a set of bilsteins on all round and the handling is wonderful

_________________
If you can keep your head, while all around are loosing theirs. You've probably misunderstood whats happening.

'72 Fasty in progress as ever HERE
'85 944 works more than it doesnt
'05 Octavia Estate Diesel POWER!
'82 Mini


Top
 Profile  
Reply with quote  
 Post subject: Re: 944 2.5 big end shells
PostPosted: Mon Jul 16, 2018 4:25 pm 
Offline

Joined: Tue Nov 19, 2013 11:48 am
Posts: 1668
Location: West Essex
TIPEC membership: 0
Loose crank pulley?
OPRV playing up?

Have you tried FPS for shells (Ferrari’s Piston Service)

And as for Porsche parts prices, just wait till they are the only place to get bits, and the cars have classic status I can see 3-4 times the price they are now

_________________
Cobalt Blue 968 Coupe 1992


Top
 Profile  
Reply with quote  
 Post subject: Re: 944 2.5 big end shells
PostPosted: Mon Jul 16, 2018 4:43 pm 
Offline

Joined: Tue Nov 06, 2007 12:22 am
Posts: 1390
Location: Stratford-upon-Avon
TIPEC membership: 4635
broady_6 wrote:

Then i noticed the 0.25 stamp on a shell, it seems very hard to get oversize big end shells and i rang Porsche today who quoted £221+vat. Which is mental! Why are they 5 times the price??? Surely as the cars age more and more till need the oversize?


I’m strictly a 928 guy so don’t know about 944 bearing price/availability, but as these engines wear wouldn’t they require undersized not oversized bearings if crank needs grinding?

_________________
928 S4 Amazon Green 91MY


Top
 Profile  
Reply with quote  
 Post subject: Re: 944 2.5 big end shells
PostPosted: Mon Jul 16, 2018 5:00 pm 
Offline

Joined: Fri Nov 23, 2012 10:41 pm
Posts: 804
Location: Lincs
TIPEC membership: 6726
Crank pulley is ft! Checked the oprv already.

I haven't, but ta for the tip, ill give them a call.

I have always found Porsche prices very reasonable. I buy from them quite often, silly buts like arb bushes which are £4 ect. It just seems 1 part in 10 is suddenly 5 times the price it should be.

You are correct sir, its a terminology thing. I had been asking for 0.25 undersize bearing. But every reply i got they were called oversize. I guess the bearing is thicker, there for oversize. Esther than referring to the crank pin which is 0.25 smaller diameter.

Either way they're a kings random!

With one shell showing copper i guess i have no choice but to replace them. It's just finding a set at a realistic price

_________________
If you can keep your head, while all around are loosing theirs. You've probably misunderstood whats happening.

'72 Fasty in progress as ever HERE
'85 944 works more than it doesnt
'05 Octavia Estate Diesel POWER!
'82 Mini


Top
 Profile  
Reply with quote  
 Post subject: Re: 944 2.5 big end shells
PostPosted: Mon Jul 16, 2018 5:09 pm 
Offline

Joined: Sun Nov 04, 2012 12:49 pm
Posts: 93
TIPEC membership: 0
Might be the gauge that is faulty - had this in my turbo. Oil pressure dropped as throttle applied (and boost arrived). I fitted a separate oil pressure sender & gauge to confirm this was the case.


Top
 Profile  
Reply with quote  
 Post subject: Re: 944 2.5 big end shells
PostPosted: Mon Jul 16, 2018 5:47 pm 
Offline

Joined: Fri Nov 23, 2012 10:41 pm
Posts: 804
Location: Lincs
TIPEC membership: 6726
edh wrote:
Might be the gauge that is faulty - had this in my turbo. Oil pressure dropped as throttle applied (and boost arrived). I fitted a separate oil pressure sender & gauge to confirm this was the case.



You might be right. this could have always been the case. but behavior has defiantly changed. With the small metal flecks in the oil and the lack of anything on the magnetic sump plug. Im more and more starting to believe its the bearings sacrificing them selves as they're supposed to to save the real metal parts.

In this video around 6 seconds you will seethe needle bouncing. It has been worse than that.

video removed

_________________
If you can keep your head, while all around are loosing theirs. You've probably misunderstood whats happening.

'72 Fasty in progress as ever HERE
'85 944 works more than it doesnt
'05 Octavia Estate Diesel POWER!
'82 Mini


Last edited by broady_6 on Sun Jul 29, 2018 10:25 pm, edited 2 times in total.

Top
 Profile  
Reply with quote  
 Post subject: Re: 944 2.5 big end shells
PostPosted: Sat Jul 21, 2018 3:17 pm 
Offline

Joined: Fri Nov 23, 2012 10:41 pm
Posts: 804
Location: Lincs
TIPEC membership: 6726
Well if youre anything like we, you'll be well hacked off having a problem, using the wonderful internet to research folks whos have similar issues only to find none of them bothered to finish their threads and left you frustrated.

So even if no one cares im going to keep posting in this :P

I managed to get myself a set of big end shells NOS from germany over £100 cheaper than new from Porsche. Im still struggling to find a smoking gun for this one though.
The crank pins all measure up within spec, some are close to the lower limit but they are still inside it. with out removing the pistons I cant be accurate but the little ends feel as they should. No wobble, they slide on the pin freely.


For some reason my mind drifted to the oil pump drive, the bolt was defiantly tight (the usual effort to remove it), but I remembered that id removed the power steering pulley a number of years ago (4 or 5 iirs) as my car has a manual rack. I wondered if I may should have put a washer in of the same thickness and couldn’t recall if it did so I decided to check.

Ive taken the plunge and pulled the rad out and belts off. There was no sign of slipping on the oil pump drive gear or the crank gear. I did a spot of googling and looked in the IPC only to see there should be a washer between the drive gear and the crank cambelt gear.

Image

Item 21

I had put this washer under 15. I cant see this having made the difference between oil pressure and fluctuation oil pressure, fortunately I have a spare washer so I will run both washers to compensate for the pulley thickness. One in the correct place (21) and the other where it always was (15).

Silver linings and all that, it seems the missing washer is supposed to step the gear away from the back of the belt case. My belt has been running against that and taken the edge off. So its firmly in the bin and a new one is on the way. So at least its prevented a snapped belt and £££ valves in the future

So to this end I have little more time to spend on this now, so im going to pop the cam box off while the belts off, check and hope its all ok then clean it all up, fit the new shell and belt and see how it runs. If its still not right then it will be parked untill my other cars resto is done and then I will take the engine out and do a full strip down

Only 1 question for your guys, is the IPC showing item 12 the correct way around, should facign away from the engine?

I hope this will be of value to someone one day!

_________________
If you can keep your head, while all around are loosing theirs. You've probably misunderstood whats happening.

'72 Fasty in progress as ever HERE
'85 944 works more than it doesnt
'05 Octavia Estate Diesel POWER!
'82 Mini


Top
 Profile  
Reply with quote  
 Post subject: Re: 944 2.5 big end shells
PostPosted: Sat Jul 28, 2018 9:08 pm 
Offline

Joined: Fri Nov 23, 2012 10:41 pm
Posts: 804
Location: Lincs
TIPEC membership: 6726
Well im not exactly any the wiser. rebuild with new big end shells and im getting this kinda reading at a constant 60mph.

Its more stable than previously (it was flicking 3-5bar) at times but its still fluttering.

https://www.youtube.com/watch?v=L0O1Y7L ... e=youtu.be

So an improvement but not a fix. I have two oil pressure sender, one the original and one after market. I have had both fitted to the car, I have disconnected the wire to the gauge and connected my multimeter this is giving the variable read out, so this this leads me to believe that the wiring and gauge on the car are fine. I can only assume I have two dodgy pressure senders or a poorly oil pump?

Anyone care to comment?

_________________
If you can keep your head, while all around are loosing theirs. You've probably misunderstood whats happening.

'72 Fasty in progress as ever HERE
'85 944 works more than it doesnt
'05 Octavia Estate Diesel POWER!
'82 Mini


Last edited by broady_6 on Sun Jul 29, 2018 10:24 pm, edited 1 time in total.

Top
 Profile  
Reply with quote  
 Post subject: Re: 944 2.5 big end shells
PostPosted: Sat Jul 28, 2018 11:41 pm 
Offline

Joined: Tue Nov 19, 2013 11:48 am
Posts: 1668
Location: West Essex
TIPEC membership: 0
I would personally forget the gauge in the car and fit an analog oil line fed one to make sure the engine pressure is stable, then go looking for electrical or mechanical failures

Can you borrow another OPRV as I believe there was an update to the older type for this reason

_________________
Cobalt Blue 968 Coupe 1992


Top
 Profile  
Reply with quote  
 Post subject: Re: 944 2.5 big end shells
PostPosted: Sat Jul 28, 2018 11:56 pm 
Offline

Joined: Fri Nov 23, 2012 10:41 pm
Posts: 804
Location: Lincs
TIPEC membership: 6726
Just this very day I've ordered an M18 adapter to plumb my gauge in. Great minds think a like! Seems the gauge in the car is correctly outputting the information its getting from the sender.

Could well be the pressure valve, i guess if it was momentarily sticking there would be a big spike in pressure which would fire the valve a long way open then causing a big drop in pressure. Which seems to be what I'm seeing.

I've no one local with a car anymore to borrow on from. You're right there was an upgrade, id never known why. But if this is the reason, then i need the upgrade as I'm still running the old piston and spring type.

Mind you £300 for a new one makes the eyes water

_________________
If you can keep your head, while all around are loosing theirs. You've probably misunderstood whats happening.

'72 Fasty in progress as ever HERE
'85 944 works more than it doesnt
'05 Octavia Estate Diesel POWER!
'82 Mini


Top
 Profile  
Reply with quote  
 Post subject: Re: 944 2.5 big end shells
PostPosted: Sun Jul 29, 2018 5:33 pm 
Offline

Joined: Tue Nov 19, 2013 11:48 am
Posts: 1668
Location: West Essex
TIPEC membership: 0
I have seen a few housings with the OPRV still in up for sale, other than that try giving Kevin at EMC a call they might have one, place is a gold mine for 944/968 bits

_________________
Cobalt Blue 968 Coupe 1992


Top
 Profile  
Reply with quote  
 Post subject: Re: 944 2.5 big end shells
PostPosted: Sun Jul 29, 2018 6:31 pm 
Offline

Joined: Fri Nov 23, 2012 10:41 pm
Posts: 804
Location: Lincs
TIPEC membership: 6726
Cheers ill keep any eye out and give them a call. what happened to porkapart?

_________________
If you can keep your head, while all around are loosing theirs. You've probably misunderstood whats happening.

'72 Fasty in progress as ever HERE
'85 944 works more than it doesnt
'05 Octavia Estate Diesel POWER!
'82 Mini


Top
 Profile  
Reply with quote  
 Post subject: Re: 944 2.5 big end shells
PostPosted: Sun Jul 29, 2018 9:05 pm 
Offline

Joined: Wed Apr 18, 2012 8:26 am
Posts: 241
TIPEC membership: 0
I think I might have one spare ,I will check the garage tommorow .
Just to confirm this is the shorter of the two styles of oprv ?


Top
 Profile  
Reply with quote  
 Post subject: Re: 944 2.5 big end shells
PostPosted: Sun Jul 29, 2018 9:08 pm 
Offline

Joined: Fri Nov 23, 2012 10:41 pm
Posts: 804
Location: Lincs
TIPEC membership: 6726
Yeah that's my understanding too. Fig A being for earlier cars

Image

Very good of you sir! Let me know if you have.

_________________
If you can keep your head, while all around are loosing theirs. You've probably misunderstood whats happening.

'72 Fasty in progress as ever HERE
'85 944 works more than it doesnt
'05 Octavia Estate Diesel POWER!
'82 Mini


Top
 Profile  
Reply with quote  
 Post subject: Re: 944 2.5 big end shells
PostPosted: Sun Jul 29, 2018 9:18 pm 
Offline

Joined: Wed Apr 18, 2012 8:26 am
Posts: 241
TIPEC membership: 0
Hi , just checked and have one of each , pm me your address and I will post you the shorter one to try .
Simon


Top
 Profile  
Reply with quote  
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 45 posts ]  Go to page 1, 2, 3  Next

All times are UTC [ DST ]


Who is online

Users browsing this forum: Google [Bot] and 25 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group