scot's 82 part euro 4.7 rebuild update
04-24-2005, 01:23 PM
#1
Rennlist Member
Thread Starter
scot's 82 part euro 4.7 rebuild update
Well, we have got the engine almost all apart. (we have to split the block and get the crank out now)
removed the two pistons with rods (#2-6) and the pistons look good. the heads look good to, but number 6, suspicioiusly has a lightly colored tan exhaust valve, while all the other 15 valves are all black/grey. anyone know how this could happen. its plug looks ok, and the piston looks fine too. hope its not burned.
take a look at the valve springs and retainers . doesnt look stock.
Anyway, we still have a lot of work to get the pistons and crank out.
Now the question becomes, what caused the #2-6 bearing to sieze only after 2.5 hours of running 1 hour of track time. there was a lot of metal melted into the oiling hole in the crank, but there was some black sludge too. the engine had a lot of grey slug when we started, but most of the engine upon disassembly looks pretty new ( ie gaskets are all very new looking)
one of the pulled pistons had a couple of ring gaps close together rather than the 120 degree offset. also, the pistons were stamped with a very small 97.465 and none of the standard large #1 stamped pistons series numbers. wonder if it was a rebuild with oversized pistons (in the little white book, 97.465 is the first oversize ) bore measures about 97.5 with a digital micrometer.
Im hoping that the crank was clogged and thats the reason for the failure. Otherwise, we are putting a new crank in and new bearings, so barring some kind of major oiling issue, like the pump, we should be ok, right? (what do i know!?
Here are some pics
Mk
ps we got the main crank bolt off with my NOS bottle and a air gun. just turned the regulator pressure up to about 200psi and it seemed to work well. that bottle has lasted for a season of air for the tires and some light air tools and it still has about 1lb of NOS left out of 7lbs i started with.
removed the two pistons with rods (#2-6) and the pistons look good. the heads look good to, but number 6, suspicioiusly has a lightly colored tan exhaust valve, while all the other 15 valves are all black/grey. anyone know how this could happen. its plug looks ok, and the piston looks fine too. hope its not burned.
take a look at the valve springs and retainers . doesnt look stock.
Anyway, we still have a lot of work to get the pistons and crank out.
Now the question becomes, what caused the #2-6 bearing to sieze only after 2.5 hours of running 1 hour of track time. there was a lot of metal melted into the oiling hole in the crank, but there was some black sludge too. the engine had a lot of grey slug when we started, but most of the engine upon disassembly looks pretty new ( ie gaskets are all very new looking)
one of the pulled pistons had a couple of ring gaps close together rather than the 120 degree offset. also, the pistons were stamped with a very small 97.465 and none of the standard large #1 stamped pistons series numbers. wonder if it was a rebuild with oversized pistons (in the little white book, 97.465 is the first oversize ) bore measures about 97.5 with a digital micrometer.
Im hoping that the crank was clogged and thats the reason for the failure. Otherwise, we are putting a new crank in and new bearings, so barring some kind of major oiling issue, like the pump, we should be ok, right? (what do i know!?
Here are some pics
Mk
ps we got the main crank bolt off with my NOS bottle and a air gun. just turned the regulator pressure up to about 200psi and it seemed to work well. that bottle has lasted for a season of air for the tires and some light air tools and it still has about 1lb of NOS left out of 7lbs i started with.
04-24-2005, 01:33 PM
#2
Drifting
Other 17 valves? Now I know how you are trying to get more power out of it!
When we crossdrill a crank, we drill out all the plugs and clean out all the oil passages. You would not believe all the crud we get out of the cranks even after they have been "professionally" cleaned. It is usually a black carbon like material that is very hard, comes out like a powder.
It's quite possible that you had a restricted flow crank to start with and racing pushed it over it's limited flow capacity.
When we crossdrill a crank, we drill out all the plugs and clean out all the oil passages. You would not believe all the crud we get out of the cranks even after they have been "professionally" cleaned. It is usually a black carbon like material that is very hard, comes out like a powder.
It's quite possible that you had a restricted flow crank to start with and racing pushed it over it's limited flow capacity.
04-24-2005, 01:39 PM
#3
Rennlist Member
Thread Starter
ha ha. my calculator (brain) must have added one vave to 16 vs subtracting.
(corrected!)
So, when i get a new "used" crank, what can you do to make sure its going to flow right and not have cloggs?
the stuff that came out of the hole was melted bearing . It looked like a plug! but on the backside of the plug, the black carbon/sludge, looks like it could have caused the failure. wish i had more experience in this engine forensics.
if the main chance of a problem is the crank, at least we are removing that from the equation.
mk
(corrected!)
So, when i get a new "used" crank, what can you do to make sure its going to flow right and not have cloggs?
the stuff that came out of the hole was melted bearing . It looked like a plug! but on the backside of the plug, the black carbon/sludge, looks like it could have caused the failure. wish i had more experience in this engine forensics.
if the main chance of a problem is the crank, at least we are removing that from the equation.
mk
Originally Posted by Ketchmi
Other 17 valves? Now I know how you are trying to get more power out of it!
When we crossdrill a crank, we drill out all the plugs and clean out all the oil passages. You would not believe all the crud we get out of the cranks even after they have been "professionally" cleaned. It is usually a black carbon like material that is very hard, comes out like a powder.
It's quite possible that you had a restricted flow crank to start with and racing pushed it over it's limited flow capacity.
When we crossdrill a crank, we drill out all the plugs and clean out all the oil passages. You would not believe all the crud we get out of the cranks even after they have been "professionally" cleaned. It is usually a black carbon like material that is very hard, comes out like a powder.
It's quite possible that you had a restricted flow crank to start with and racing pushed it over it's limited flow capacity.
04-24-2005, 01:55 PM
#4
Drifting
Geez, now I need to edit my post about 17 valves.
When we crossdrill a crank, we drill out all the plugs and clean out all the oil passages.
It only takes a few hours to crossdrill, remove plugs, clean passages and tap the holes for screw in plugs. Cheap insurance for anything put on a track. A bit of "piece of mind" doesn't hurt either, one less thing to worry about on those long sweepers in low gears. Give me a call this coming week and we'll see what we can do for you. If you need a crank, we have quite a few lying around as well as rods that may match your existing ones. I'm still deciding exactly how to build my 4.5L track engine for my light weight car but I have a lot of cores to work with.
When we crossdrill a crank, we drill out all the plugs and clean out all the oil passages.
It only takes a few hours to crossdrill, remove plugs, clean passages and tap the holes for screw in plugs. Cheap insurance for anything put on a track. A bit of "piece of mind" doesn't hurt either, one less thing to worry about on those long sweepers in low gears. Give me a call this coming week and we'll see what we can do for you. If you need a crank, we have quite a few lying around as well as rods that may match your existing ones. I'm still deciding exactly how to build my 4.5L track engine for my light weight car but I have a lot of cores to work with.
04-24-2005, 07:30 PM
#5
Rennlist Member
Thread Starter
Hey, dont worry about it! ill admit to the 18 valver mispost.
anyway, 928 intl said they will take care of most all of the parts, but thanks for the offer.
If you are interested in building up that 4.5, and need euro intake, we have a REAL nice one! (polished external, extrude honed and the euro throttle body)
so, what do we need to do for cross drilling .. take it to a machine shop? i did notice that the crank has a two holes, and you can see through them (inline) does that mean its already cross drilled?
could cross drilling cause an issue of flow pressure reduction to the bearing in some cases?
mk
anyway, 928 intl said they will take care of most all of the parts, but thanks for the offer.
If you are interested in building up that 4.5, and need euro intake, we have a REAL nice one! (polished external, extrude honed and the euro throttle body)
so, what do we need to do for cross drilling .. take it to a machine shop? i did notice that the crank has a two holes, and you can see through them (inline) does that mean its already cross drilled?
could cross drilling cause an issue of flow pressure reduction to the bearing in some cases?
mk
Originally Posted by Ketchmi
Geez, now I need to edit my post about 17 valves.
When we crossdrill a crank, we drill out all the plugs and clean out all the oil passages.
It only takes a few hours to crossdrill, remove plugs, clean passages and tap the holes for screw in plugs. Cheap insurance for anything put on a track. A bit of "piece of mind" doesn't hurt either, one less thing to worry about on those long sweepers in low gears. Give me a call this coming week and we'll see what we can do for you. If you need a crank, we have quite a few lying around as well as rods that may match your existing ones. I'm still deciding exactly how to build my 4.5L track engine for my light weight car but I have a lot of cores to work with.
When we crossdrill a crank, we drill out all the plugs and clean out all the oil passages.
It only takes a few hours to crossdrill, remove plugs, clean passages and tap the holes for screw in plugs. Cheap insurance for anything put on a track. A bit of "piece of mind" doesn't hurt either, one less thing to worry about on those long sweepers in low gears. Give me a call this coming week and we'll see what we can do for you. If you need a crank, we have quite a few lying around as well as rods that may match your existing ones. I'm still deciding exactly how to build my 4.5L track engine for my light weight car but I have a lot of cores to work with.
04-25-2005, 02:03 PM
#6
Rennlist Member
Thread Starter
anyone notice the valves springs. any idea what they are? Kind of purple in color
Plus, the valves are labled TRW, would that be stock, they dont look like the euro valves ive replaced in the past.
Plus, the valves are labled TRW, would that be stock, they dont look like the euro valves ive replaced in the past.