Hi All,
It’s been a while since I’ve posted any threads on motors, I think the last one was where my engine was out getting what I thought would be sorted once and for all. But alas it was not to be, I got the car back and within weeks of spending £2900 on repairs the old problem reared its head again and I had oil mixing with my water. But this was not all, since the last big bill I now had a rip in my roof and serious problems with the wheels/suspension which was causing big problems with the way the car gets down the road.
For those of you that don’t know the car here is a picture of what it looks like
I parked the car up in my garage and left it for 4 or 5 months while deciding what to do, but was always keeping my ears open for an opportunity to find workshop space and or somebody who was willing to help me get this thing fixed. I was not ready to give up on the old girl just yet.
A few weeks ago such an opportunity came up, the story is a long one so I won’t go into it but the outcome was somebody that I can trust was willing to give up space and his time so that work could commence on my poorly old 911. Now I should point out that not all the work is being done by me but I have been inspecting the car and helping where I can around my own work schedule.
Having read the autofarm pdf about my engine: http://www.autofarm.co.uk/pdf/Total911_July06.pdf and being well aware of the issues I have, I am still convinced that my cylinder head on the left hand side is the cause of the cars problems so that was the first thing that I wanted tested but It means a massive commitment in stripping the engine block right down to the bottom end.
First of all we got the car up on the ramp and removed the bumper and the manifolds, normally on an old Porsche this job would be a royal pain in the arse because the manifold bolts are notorious for rusting away, but on my car this was easy as I had them drilled out and refitted with captive nut alloy replacements last time the engine was out. Good start… until you look up the manifold on the left hand side and see signs of water inside the cylinder head which is not so good and difficult to get pictures of. So I didn’t but here are a couple of the car up on the ramp.
Next up was getting the engine on a bench and stripping it down exposing all of the tasty bits while getting both heads sent to a specialist to be looked at, pressure tested for cracks, skimmed if they were good and sent back. So that’s what happened and my heads should be back with me on Monday. The bad news is that my suspicions have been confirmed and the old left hand head is toast, it’s got a terminal crack that runs from a bolted face where it meets the hydraulic tappets across to a core plug, I’ll get some pics of this when I get it back.
Meanwhile I have been busy locating a new head and yesterday I struck gold and found a head in Yorkshire that is apparently in good shape with no cracks and will be shipped to me in the week, it comes from a car of the same age and roughly the same mileage as my car. Speaking to the guy he tells me it was from his old engine which had problems with the bottom end, he assures me that the head is in good shape, but the only down side is that it has a manifold attached to it as the bolts are corroded. So I decide to go for it and will removed the manifold and then get the head sent to be checked for cracks and be skimmed before it goes on the car. £500 for the part seemed a reasonable price as well, if it really is in as good shape as the guy claims.
The next thing to do while the engine is in pieces on the bench is to inspect some of the other parts of this engine to get an idea of what I’m in for in rebuild costs so let’s start with a few pictures of what we are looking at.
Here is the block on a bench with the heads removed looking at it from the front.
All the pulleys are in great shape no groaning bearings, new oil cooler waiting to be fitted at the top right under the blue towel, this was replaced just a few months back but I’m putting another new one on this anyway.
My biggest fear was looking at the bores and seeing scores or worse cracks. But when you get up close and take a look they are in really great shape, no scores at all and no cracking, pistons also look in great shape. This is the left hand side where we have cylinder head issues:
While we are on the main block let’s take a look around the back of the block where the RMS (rear main seal) and IMS (Intermediate shaft)are located, these are the weak points in the block so it’s good to at least inspect them and decide what to do while the engine is in pieces.
First up the RMS which is normally hidden behind the dual mass flywheel, more on this later:
The RMS looks in good enough nick but is weeping a little so we are going to replace it while the engine is in pieces.
Next up down the bottom of the block we have the IMS:
Looks pretty nasty down there, so we take it off with a 10mi and a screwdriver then remove the flange cover to expose the ims bearing:
Now if you know your Porsches you know that this little bugger is the bane of any 996 or 986 owners life and I’m sure it has been the cause of many sleepless nights, if it gives way the bottom end of these engines is normally toast. Now if there are issues you can feel play in the bearing while it is in situ, my one however is rock solid with no discernible play, nether the less I decided to see what is out there and have found a company that sell an uprated bearing called an LN engineering ceramic ball bearing. The company is called revolution Porsche and I had a lengthy conversation with a guy from there tonight about the bearing and am deciding what I want to do with it. The LN unit is £400 +vat and requires a special tool to fit. Or as my unit looks in good shape do I just leave it?... Decisions… I’m not sure just yet but will decide in the week.
Next up its time to inspect the cams and variocam system, again the cams are showing little wear and the cam lobes are still in great condition. All of the sprockets also look good with no signs of cracks or damage.
Next up clutch and dual mass flywheel:
The flywheel is in great shape but the underside of the clutch is basically on metal so a new clutch is needed when it goes back together:
The release bearing is also shot so will need replacing its grinding away up there.
So what are we left with, well this is a box of the good bits the rockers are fine, and will need new gaskets, the head bolts will need replacing, I almost fell off my chair when I was told the bolts are the best part of £10 each, seems reasonable until you realise you need 24 of them.
Right now that is where I am at with the car, I am sure I will tally up total costs at the end but so far in parts alone I have spent a small fortune but at least this time when it goes back together I will have personally looked at every part of the engine and know exactly what condition it is in.
It’s been a while since I’ve posted any threads on motors, I think the last one was where my engine was out getting what I thought would be sorted once and for all. But alas it was not to be, I got the car back and within weeks of spending £2900 on repairs the old problem reared its head again and I had oil mixing with my water. But this was not all, since the last big bill I now had a rip in my roof and serious problems with the wheels/suspension which was causing big problems with the way the car gets down the road.
For those of you that don’t know the car here is a picture of what it looks like
I parked the car up in my garage and left it for 4 or 5 months while deciding what to do, but was always keeping my ears open for an opportunity to find workshop space and or somebody who was willing to help me get this thing fixed. I was not ready to give up on the old girl just yet.
A few weeks ago such an opportunity came up, the story is a long one so I won’t go into it but the outcome was somebody that I can trust was willing to give up space and his time so that work could commence on my poorly old 911. Now I should point out that not all the work is being done by me but I have been inspecting the car and helping where I can around my own work schedule.
Having read the autofarm pdf about my engine: http://www.autofarm.co.uk/pdf/Total911_July06.pdf and being well aware of the issues I have, I am still convinced that my cylinder head on the left hand side is the cause of the cars problems so that was the first thing that I wanted tested but It means a massive commitment in stripping the engine block right down to the bottom end.
First of all we got the car up on the ramp and removed the bumper and the manifolds, normally on an old Porsche this job would be a royal pain in the arse because the manifold bolts are notorious for rusting away, but on my car this was easy as I had them drilled out and refitted with captive nut alloy replacements last time the engine was out. Good start… until you look up the manifold on the left hand side and see signs of water inside the cylinder head which is not so good and difficult to get pictures of. So I didn’t but here are a couple of the car up on the ramp.
Next up was getting the engine on a bench and stripping it down exposing all of the tasty bits while getting both heads sent to a specialist to be looked at, pressure tested for cracks, skimmed if they were good and sent back. So that’s what happened and my heads should be back with me on Monday. The bad news is that my suspicions have been confirmed and the old left hand head is toast, it’s got a terminal crack that runs from a bolted face where it meets the hydraulic tappets across to a core plug, I’ll get some pics of this when I get it back.
Meanwhile I have been busy locating a new head and yesterday I struck gold and found a head in Yorkshire that is apparently in good shape with no cracks and will be shipped to me in the week, it comes from a car of the same age and roughly the same mileage as my car. Speaking to the guy he tells me it was from his old engine which had problems with the bottom end, he assures me that the head is in good shape, but the only down side is that it has a manifold attached to it as the bolts are corroded. So I decide to go for it and will removed the manifold and then get the head sent to be checked for cracks and be skimmed before it goes on the car. £500 for the part seemed a reasonable price as well, if it really is in as good shape as the guy claims.
The next thing to do while the engine is in pieces on the bench is to inspect some of the other parts of this engine to get an idea of what I’m in for in rebuild costs so let’s start with a few pictures of what we are looking at.
Here is the block on a bench with the heads removed looking at it from the front.
All the pulleys are in great shape no groaning bearings, new oil cooler waiting to be fitted at the top right under the blue towel, this was replaced just a few months back but I’m putting another new one on this anyway.
My biggest fear was looking at the bores and seeing scores or worse cracks. But when you get up close and take a look they are in really great shape, no scores at all and no cracking, pistons also look in great shape. This is the left hand side where we have cylinder head issues:
While we are on the main block let’s take a look around the back of the block where the RMS (rear main seal) and IMS (Intermediate shaft)are located, these are the weak points in the block so it’s good to at least inspect them and decide what to do while the engine is in pieces.
First up the RMS which is normally hidden behind the dual mass flywheel, more on this later:
The RMS looks in good enough nick but is weeping a little so we are going to replace it while the engine is in pieces.
Next up down the bottom of the block we have the IMS:
Looks pretty nasty down there, so we take it off with a 10mi and a screwdriver then remove the flange cover to expose the ims bearing:
Now if you know your Porsches you know that this little bugger is the bane of any 996 or 986 owners life and I’m sure it has been the cause of many sleepless nights, if it gives way the bottom end of these engines is normally toast. Now if there are issues you can feel play in the bearing while it is in situ, my one however is rock solid with no discernible play, nether the less I decided to see what is out there and have found a company that sell an uprated bearing called an LN engineering ceramic ball bearing. The company is called revolution Porsche and I had a lengthy conversation with a guy from there tonight about the bearing and am deciding what I want to do with it. The LN unit is £400 +vat and requires a special tool to fit. Or as my unit looks in good shape do I just leave it?... Decisions… I’m not sure just yet but will decide in the week.
Next up its time to inspect the cams and variocam system, again the cams are showing little wear and the cam lobes are still in great condition. All of the sprockets also look good with no signs of cracks or damage.
Next up clutch and dual mass flywheel:
The flywheel is in great shape but the underside of the clutch is basically on metal so a new clutch is needed when it goes back together:
The release bearing is also shot so will need replacing its grinding away up there.
So what are we left with, well this is a box of the good bits the rockers are fine, and will need new gaskets, the head bolts will need replacing, I almost fell off my chair when I was told the bolts are the best part of £10 each, seems reasonable until you realise you need 24 of them.
Right now that is where I am at with the car, I am sure I will tally up total costs at the end but so far in parts alone I have spent a small fortune but at least this time when it goes back together I will have personally looked at every part of the engine and know exactly what condition it is in.
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back when i first passed my test 20 odd years ago 
.Hope this new head turns out to be a good one for you.
