Engine Health Check/Inspection. AJP8 Technical Info please!
Discussion
As my body-off refurb is coming along, slowly, I'm pondering what to do with the engine whilst it's out. It's a '96 engine and has done 83000 miles without, as far as I can tell, any work done bar standard servicing. I certainly don't have any paperwork with the car to evidence any engine work. If the valve shims continue to wear at their current rate I might be looking at a top end rebuild by 100k miles, equally the rate of wear might slow down & extend the engine's life, who knows. The chassis is off being blasted and painted at the moment & I've replaced all the heatshield on the car. Once I've got the chassis back on the car and the garage tidied up a bit I expect to have some space and time to have a look at the engine.
I'm sure other options are available, including 'just leave it alone', up to 'deep pockets rebuild to 4.7'. I don't have the cash for an engine rebuild on a whim, so that option is out but I'd like to do what I can to learn/further my spannering abilities in general and learn something about the state of my engine in particular.
Whilst I've not opened an engine up before I'm hoping that a bit of advice from some more experienced spanner turners on PH will enable me to further my knowledge; specifically, what I need to check, in some cases I'm sure, how to do it. I'm equipped with a torque wrench, digital calipers, a micrometer and a decent socket set. I've also rebuilt the T5 gearbox, and, with some helpful suggestions from PH, got the body off, so I'd like to think I'm not a complete novice anymore.
I'm thinking I might as well do the valve clearances again, and change the cam chain. Whilst the front cover is off I'm tempted to get the sump off for a look & clean up if there is any gunk that can be removed. That also opens up the option of checking big end and main bearing clearances. Should I do this with plastigauge? I know the engine build manual specifies tolerances at build but does anyone have some service limits for clearances, crank journal dimensions (diameter, ovality, taper, anything else).
What else can I check? I suppose I could check piston-bore clearance and/or ring gap but that would have to be at BDC so I'm not sure how useful it'd be. Thoughts? Info? Whats an acceptable tolerance for an engine that's in use, and whats considered 'past it'?
Valve guide wear seems to be another issues found when engines are stripped for rebuild. Any way I could get some assessment of that without taking the heads off? Also, what's acceptable and whats not?
I also do have an engine leakdown tester, but it's a cheap ebay effort so whilst I could have a go I'm not sure how much faith I should have in any results it gives me.
I'm sure other options are available, including 'just leave it alone', up to 'deep pockets rebuild to 4.7'. I don't have the cash for an engine rebuild on a whim, so that option is out but I'd like to do what I can to learn/further my spannering abilities in general and learn something about the state of my engine in particular.
Whilst I've not opened an engine up before I'm hoping that a bit of advice from some more experienced spanner turners on PH will enable me to further my knowledge; specifically, what I need to check, in some cases I'm sure, how to do it. I'm equipped with a torque wrench, digital calipers, a micrometer and a decent socket set. I've also rebuilt the T5 gearbox, and, with some helpful suggestions from PH, got the body off, so I'd like to think I'm not a complete novice anymore.
I'm thinking I might as well do the valve clearances again, and change the cam chain. Whilst the front cover is off I'm tempted to get the sump off for a look & clean up if there is any gunk that can be removed. That also opens up the option of checking big end and main bearing clearances. Should I do this with plastigauge? I know the engine build manual specifies tolerances at build but does anyone have some service limits for clearances, crank journal dimensions (diameter, ovality, taper, anything else).
What else can I check? I suppose I could check piston-bore clearance and/or ring gap but that would have to be at BDC so I'm not sure how useful it'd be. Thoughts? Info? Whats an acceptable tolerance for an engine that's in use, and whats considered 'past it'?
Valve guide wear seems to be another issues found when engines are stripped for rebuild. Any way I could get some assessment of that without taking the heads off? Also, what's acceptable and whats not?
I also do have an engine leakdown tester, but it's a cheap ebay effort so whilst I could have a go I'm not sure how much faith I should have in any results it gives me.
I cannot comment on your engine specifically as I know very little about them.
However, I hope these general engine comments are of help to you. If you take the engine apart it is very easy to land up spending a lot of money on it. It is out the car anyway. You have taken it apart anyway. Why would you build it up again using old parts which have wear on them? I know someone who landed up doing a full re-build (at great expenses) just because the engine was out anyway. There was nothing wrong with his engine to start with.
On the other hand, if you don't do anything and just put it back in the car as is, and a year later you have engine issues, then you will ask yourself why you didn't address these at this stage. Only you can balance this against spending time and money now.
Currently my body is off and I checked the cam shaft as they are a known weak point on the rover V8, and the clutch as that is much easier to change when the engine is out. The camshaft was fine, but the clutch was looking like it was at the end of its life so it has been changed. I purposefully have not taken the engine apart other than that. It was running fine when the car was last on the road and if in a year or two I have to take it out for serious work, then so be it. For my body off project, I cannot afford to change everything "just in case" and nor can I afford to turn it into a brand new car.
I believe the valve gear is the weak point on your engines, so I would definitely want to check valve clearances. You should also check the clutch condition as that is easy to change now and expensive if you have to later. I am sure some experts will be along in a minute and list everything you can or should check on your engine. But, be warned, if you strip it down just to take a look, you will land up spending a fortune on it.
However, I hope these general engine comments are of help to you. If you take the engine apart it is very easy to land up spending a lot of money on it. It is out the car anyway. You have taken it apart anyway. Why would you build it up again using old parts which have wear on them? I know someone who landed up doing a full re-build (at great expenses) just because the engine was out anyway. There was nothing wrong with his engine to start with.
On the other hand, if you don't do anything and just put it back in the car as is, and a year later you have engine issues, then you will ask yourself why you didn't address these at this stage. Only you can balance this against spending time and money now.
Currently my body is off and I checked the cam shaft as they are a known weak point on the rover V8, and the clutch as that is much easier to change when the engine is out. The camshaft was fine, but the clutch was looking like it was at the end of its life so it has been changed. I purposefully have not taken the engine apart other than that. It was running fine when the car was last on the road and if in a year or two I have to take it out for serious work, then so be it. For my body off project, I cannot afford to change everything "just in case" and nor can I afford to turn it into a brand new car.
I believe the valve gear is the weak point on your engines, so I would definitely want to check valve clearances. You should also check the clutch condition as that is easy to change now and expensive if you have to later. I am sure some experts will be along in a minute and list everything you can or should check on your engine. But, be warned, if you strip it down just to take a look, you will land up spending a fortune on it.
BIG DUNC said:
I know someone who landed up doing a full re-build (at great expenses) just because the engine was out anyway. There was nothing wrong with his engine to start with.
I don't think you are referring to me, but I am in that boat.. Because it was out I started fiddling. Now it is a big project..BIG DUNC said:
I cannot comment on your engine specifically as I know very little about them.
However, I hope these general engine comments are of help to you. If you take the engine apart it is very easy to land up spending a lot of money on it. It is out the car anyway. You have taken it apart anyway. Why would you build it up again using old parts which have wear on them? I know someone who landed up doing a full re-build (at great expenses) just because the engine was out anyway. There was nothing wrong with his engine to start with.
On the other hand, if you don't do anything and just put it back in the car as is, and a year later you have engine issues, then you will ask yourself why you didn't address these at this stage. Only you can balance this against spending time and money now.
Currently my body is off and I checked the cam shaft as they are a known weak point on the rover V8, and the clutch as that is much easier to change when the engine is out. The camshaft was fine, but the clutch was looking like it was at the end of its life so it has been changed. I purposefully have not taken the engine apart other than that. It was running fine when the car was last on the road and if in a year or two I have to take it out for serious work, then so be it. For my body off project, I cannot afford to change everything "just in case" and nor can I afford to turn it into a brand new car.
I believe the valve gear is the weak point on your engines, so I would definitely want to check valve clearances. You should also check the clutch condition as that is easy to change now and expensive if you have to later. I am sure some experts will be along in a minute and list everything you can or should check on your engine. But, be warned, if you strip it down just to take a look, you will land up spending a fortune on it.
I also agree with all of this..However, I hope these general engine comments are of help to you. If you take the engine apart it is very easy to land up spending a lot of money on it. It is out the car anyway. You have taken it apart anyway. Why would you build it up again using old parts which have wear on them? I know someone who landed up doing a full re-build (at great expenses) just because the engine was out anyway. There was nothing wrong with his engine to start with.
On the other hand, if you don't do anything and just put it back in the car as is, and a year later you have engine issues, then you will ask yourself why you didn't address these at this stage. Only you can balance this against spending time and money now.
Currently my body is off and I checked the cam shaft as they are a known weak point on the rover V8, and the clutch as that is much easier to change when the engine is out. The camshaft was fine, but the clutch was looking like it was at the end of its life so it has been changed. I purposefully have not taken the engine apart other than that. It was running fine when the car was last on the road and if in a year or two I have to take it out for serious work, then so be it. For my body off project, I cannot afford to change everything "just in case" and nor can I afford to turn it into a brand new car.
I believe the valve gear is the weak point on your engines, so I would definitely want to check valve clearances. You should also check the clutch condition as that is easy to change now and expensive if you have to later. I am sure some experts will be along in a minute and list everything you can or should check on your engine. But, be warned, if you strip it down just to take a look, you will land up spending a fortune on it.
If it is OK atm, and you haven't got funds for a "whilst you are there" then leave it for now, but just accept it will have to come out again in a few years.
Fair enough. One thing I have wondered about is whether it has had any engine work done. I have some receipts with the car but a lot of it's early life is a mystery. The dipstick is in the wrong place for a '96 car so whilst it's likely that it's simply been replaced at some point with the later style I do wonder if this car snapped it's crank early on and had a rebuild. Some of that might be hope too as it'll make any subsequent rebuild significantly cheaper (or at least one less decision to make) if it turns out I have a good large journal crank.
No, not referring to you.
I can see how it could easily happen.
As you say, if you have the funds now, it makes sense to do it now and will probably save money long term. But if you cannot afford to spend extra now, then if it was running fine before it should run fine after. I havnt done a Cerbera engine, but on most cars it is possible to get the engine out in a day. Potentially you are saving yourself two days labour by doing it now, but paying for an engine rebuild now. Alternatively you can do nothing now, but if you do need an engine rebuild while you still own this car, it will cost you an extra two days labour at that time to get the engine in and out. If you are doing that work yourself, it is just the time, not the cost of the labour.
I can see how it could easily happen.
As you say, if you have the funds now, it makes sense to do it now and will probably save money long term. But if you cannot afford to spend extra now, then if it was running fine before it should run fine after. I havnt done a Cerbera engine, but on most cars it is possible to get the engine out in a day. Potentially you are saving yourself two days labour by doing it now, but paying for an engine rebuild now. Alternatively you can do nothing now, but if you do need an engine rebuild while you still own this car, it will cost you an extra two days labour at that time to get the engine in and out. If you are doing that work yourself, it is just the time, not the cost of the labour.
If and when the time comes I'll remove and refit the engine myself. In an ideal world I'd have a 'countdown to rebuild' timer that hits 0 just before something goes catastrophically wrong, resulting in ruined heads, or block, shattered crank, etc etc.That would allow me time to have a rebuild fund sorted as well as having got maximum value out of the original engine. If I'm best off leaving it alone, but if there's some things I can do while the engine is out to assess how worn it is and how long it might have left, then great.
Hi,
I'd do some basic checks as others have described (compression, check a bearing ec.) but you could just leave it. My engine was out at about 100k to retrieve a bolt from the sump that had fallen out of the camchain guide. I asked the about rebuilding, but it was suggested that if it's working fine then leave it alone. A new camchain is worth doing as there is no official guidance for their life expectancy. My engine is now on 175k miles.
Simon
I'd do some basic checks as others have described (compression, check a bearing ec.) but you could just leave it. My engine was out at about 100k to retrieve a bolt from the sump that had fallen out of the camchain guide. I asked the about rebuilding, but it was suggested that if it's working fine then leave it alone. A new camchain is worth doing as there is no official guidance for their life expectancy. My engine is now on 175k miles.
Simon
CerbWill said:
Fair enough. One thing I have wondered about is whether it has had any engine work done. I have some receipts with the car but a lot of it's early life is a mystery. The dipstick is in the wrong place for a '96 car so whilst it's likely that it's simply been replaced at some point with the later style I do wonder if this car snapped it's crank early on and had a rebuild. Some of that might be hope too as it'll make any subsequent rebuild significantly cheaper (or at least one less decision to make) if it turns out I have a good large journal crank.
I don't believe there was any issues with my small bearing crank, it's been performing brilliantly, but I'm having to change it to the later as no engine builder will give a warranty with that crank in.Byker28i said:
I don't believe there was any issues with my small bearing crank, it's been performing brilliantly, but I'm having to change it to the later as no engine builder will give a warranty with that crank in.
Which is odd, because you'd think they be happy to warranty everything excluding the crank.ukkid35 said:
Byker28i said:
I don't believe there was any issues with my small bearing crank, it's been performing brilliantly, but I'm having to change it to the later as no engine builder will give a warranty with that crank in.
Which is odd, because you'd think they be happy to warranty everything excluding the crank.When the engine was out of mine I had the following done &-checked ,cam-wear (engine has,done 47k miles and it was deemed there are 30-40k miles left on them),uprated head gaskets ,new timing chains (the old ones had stretched),sump off to clean the bottom of the engine out,all filters cleaned out ,oil pump and water pump rebuilt...an engine 'refresh' if you like,had all the water rails renewed too.
Useful info. Thanks all. I'll replace the timing chain & see what the state of the tensioner is. Might take the opportunity to mark TDC for each bank on the crank pulley too. I can do a leakdown test and see what that shows up. I'll consider taking the sump off but I think that'd mainly be for interest more than anything else.
However, does anyone have/know of of a manual which describes the wear limits for engine components, max ring gap, piston-bore clearance, crank dimensions, crank bearing clearances etc? Even if I'm not going to check all that now it'd be useful to have for the future.
However, does anyone have/know of of a manual which describes the wear limits for engine components, max ring gap, piston-bore clearance, crank dimensions, crank bearing clearances etc? Even if I'm not going to check all that now it'd be useful to have for the future.
CerbWill said:
Useful info. Thanks all. I'll replace the timing chain & see what the state of the tensioner is. Might take the opportunity to mark TDC for each bank on the crank pulley too. I can do a leakdown test and see what that shows up. I'll consider taking the sump off but I think that'd mainly be for interest more than anything else.
However, does anyone have/know of of a manual which describes the wear limits for engine components, max ring gap, piston-bore clearance, crank dimensions, crank bearing clearances etc? Even if I'm not going to check all that now it'd be useful to have for the future.
The engine build manual..However, does anyone have/know of of a manual which describes the wear limits for engine components, max ring gap, piston-bore clearance, crank dimensions, crank bearing clearances etc? Even if I'm not going to check all that now it'd be useful to have for the future.
0.004" piston to bore clearance is one I can remember off the top of my head..
Jhonno said:
CerbWill said:
Useful info. Thanks all. I'll replace the timing chain & see what the state of the tensioner is. Might take the opportunity to mark TDC for each bank on the crank pulley too. I can do a leakdown test and see what that shows up. I'll consider taking the sump off but I think that'd mainly be for interest more than anything else.
However, does anyone have/know of of a manual which describes the wear limits for engine components, max ring gap, piston-bore clearance, crank dimensions, crank bearing clearances etc? Even if I'm not going to check all that now it'd be useful to have for the future.
The engine build manual..However, does anyone have/know of of a manual which describes the wear limits for engine components, max ring gap, piston-bore clearance, crank dimensions, crank bearing clearances etc? Even if I'm not going to check all that now it'd be useful to have for the future.
0.004" piston to bore clearance is one I can remember off the top of my head..
Thanks, I've already downloaded a copy of the engine build manual which specifies tolerances for new engines. I guess the wear limits for components are still only known by a few engine builders. I can understand why they wouldn't want to share such information but it'd be useful for assessing the state of an engine thats run for 10s of thousands of miles.
CerbWill said:
Useful info. Thanks all. I'll replace the timing chain & see what the state of the tensioner is. Might take the opportunity to mark TDC for each bank on the crank pulley too. I can do a leakdown test and see what that shows up. I'll consider taking the sump off but I think that'd mainly be for interest more than anything else.
However, does anyone have/know of of a manual which describes the wear limits for engine components, max ring gap, piston-bore clearance, crank dimensions, crank bearing clearances etc? Even if I'm not going to check all that now it'd be useful to have for the future.
I would pull the dump off and take a look at the big end and main bearings, by 83k many engines are down to the copper on the bearings and a crank polish and new bearings are not a huge amount.However, does anyone have/know of of a manual which describes the wear limits for engine components, max ring gap, piston-bore clearance, crank dimensions, crank bearing clearances etc? Even if I'm not going to check all that now it'd be useful to have for the future.
Gassing Station | Cerbera | Top of Page | What's New | My Stuff