E39 M5 - twin supercharged
Discussion
Ok summer is over for the M5, CPS sensors and spark plug change became a bit more......
Pics show the remains of the plug and shows how the piston is chipped. Head is also beat up but valves seem to have escaped damage.
The background is that the car has been bad on low rpms, rough idle and lack of power. All symptoms indicated vanos/cps. Also it would loose power after like 5km and then after a few seconds it would come back. So at the end of June I order CPS´s and other stuff. Was going to change them out and if they were not the issue, double check the vanos soldering.
So on July 7th I was driving on a local track, not really pushing the car yet since I was learning the track. Then I got a really bad vibration from the engine, sounded like bad vanos rattle for a few seconds, then went away. I went directly into pits and then home afterwards without stressing the car. Thought it was the old issue getting worse and did not want to drive the car until it was fixed.
What I believe now is that the engine ate the plug at the track.
Need to find out why.
So.....
Ordering a new piston from VAC, it´s a forged CP 10.5.
Then engine out and head off, rebuild this winter.
Annoying as hell.
Almost as annoying as the fact I just replaced all CPS´s with the engine in the car.
But to look at the bright side, this build has been rock solid for 13 fun filled years & 80k km
Pics show the remains of the plug and shows how the piston is chipped. Head is also beat up but valves seem to have escaped damage.
The background is that the car has been bad on low rpms, rough idle and lack of power. All symptoms indicated vanos/cps. Also it would loose power after like 5km and then after a few seconds it would come back. So at the end of June I order CPS´s and other stuff. Was going to change them out and if they were not the issue, double check the vanos soldering.
So on July 7th I was driving on a local track, not really pushing the car yet since I was learning the track. Then I got a really bad vibration from the engine, sounded like bad vanos rattle for a few seconds, then went away. I went directly into pits and then home afterwards without stressing the car. Thought it was the old issue getting worse and did not want to drive the car until it was fixed.
What I believe now is that the engine ate the plug at the track.
Need to find out why.
So.....
Ordering a new piston from VAC, it´s a forged CP 10.5.
Then engine out and head off, rebuild this winter.
Annoying as hell.
Almost as annoying as the fact I just replaced all CPS´s with the engine in the car.
But to look at the bright side, this build has been rock solid for 13 fun filled years & 80k km
Sad to hear this but grateful for the updates all the same.
Would still love an E39 but they are now out of the question here in Das Krapital due to the new ULEV zone ruling out most cars pre-2005. Luckily (so far at least, natch) I have managed to find a B7 S4 - not as cool a car as the E39 M5 nor capable of mischievous degrees of under-power-yaw, but V8 manual with vague room for practical considerations (an avant).
No bloody isofix and no front airbag off-switch though! I think I picked the lowest spec B7 on the market
Good luck getting this humming again - it is the only proper accompaniment to the almost equally awesome E30
Would still love an E39 but they are now out of the question here in Das Krapital due to the new ULEV zone ruling out most cars pre-2005. Luckily (so far at least, natch) I have managed to find a B7 S4 - not as cool a car as the E39 M5 nor capable of mischievous degrees of under-power-yaw, but V8 manual with vague room for practical considerations (an avant).
No bloody isofix and no front airbag off-switch though! I think I picked the lowest spec B7 on the market
Good luck getting this humming again - it is the only proper accompaniment to the almost equally awesome E30
Projects getting attention now in the garage due to Covid, taking engine apart.
Use the opportunity to detail/restore/refurb everything in the engine bay, got a small sandblasting cabinet and some very fine glass media:
Oil filter housing was looking a bit shabby after 20 years:
Cleaned up nice
Use the opportunity to detail/restore/refurb everything in the engine bay, got a small sandblasting cabinet and some very fine glass media:
Oil filter housing was looking a bit shabby after 20 years:
Cleaned up nice
Engine teardown continues....
Cleaning and refurbing parts as I go along.
Note the bracket holding the wire tube:
Now all shiny and nice:
Alot of parts to remove....
and refurb!
Almost there:
Cleaning pistons to see status/damage:
As expected, piston 7 was totally gone:
Has been detonating like crazy towards the end.....
Unfortunately there turned out to be a pair of deep scratches that did not go away when honing:
So I have ordered a new piston set from CP/VAC, 93.5mm instead of 93mm. Sleeves will be bored over to match.
I´m also sourcing a set of S62 heads from the UK that have been refurbed and have some upgraded springs from VAC.
Cleaning and refurbing parts as I go along.
Note the bracket holding the wire tube:
Now all shiny and nice:
Alot of parts to remove....
and refurb!
Almost there:
Cleaning pistons to see status/damage:
As expected, piston 7 was totally gone:
Has been detonating like crazy towards the end.....
Unfortunately there turned out to be a pair of deep scratches that did not go away when honing:
So I have ordered a new piston set from CP/VAC, 93.5mm instead of 93mm. Sleeves will be bored over to match.
I´m also sourcing a set of S62 heads from the UK that have been refurbed and have some upgraded springs from VAC.
Not much has happened in the car since the engine builder left Sunday a week ago.
We started assembly the Monday before with the bare block and there were a few WTF moments that could have gone worse....
First was when we were gapping rings and connecting rods to pistons. I had laid it all out nice on the table ready for install. "Where are the wrist pin clips" asked the engine builder. We searched the table and found none. Luckily I had not thrown the box the pistons shipped in and the box was still laying behind the sandblasting cabinet. With the clips inside!! Luckily I had not thrown the box away. Bear in mind I´m in the middle of the Atlantic and everything takes ages to ship here
Next problem was that I just could not find the chain for the oil pump. Did not look good! I was checking part numbers in Realoem when I realized it was the same chain as in the heads between the cams. So we raided one of the old heads and got a chain.
Now we were in the final stretch the night before the engine builder flew back to Denmark. Engine went in during the evening and we calibrated the throttle bodies. Then we found out the new starter was dead. Did not work.... damn. But with a little debugging it became clear it was the earth wire for the engine was not getting good enough contact on the body side. Quick fix, phew.
After the starter was cooperating it quickly became evident that the old battery was not up to starting. We connected my trusty VW Caravelle to the terminal in front (did not work trying to charge/start by connecting to the battery) but it was just not powerful enough to crank (70 Ah vs. 110 Ah) so the engine builder helped by turning the crank with a wrench while I started.
No go, would not start. Then we found out the ECU was not getting a signal from the crank sensor. Then and there, 1:30 am, I remembered we had broken the crank sensor when taking the gearbox off many many months before. And had not ordered a new one. f
k.
But believe it or not, we found one on a shelf in my garage from an order back in 2016. Replaced the sensor (that was a bh to get out, was somehow almost fused stuck) and bingo, started just before 3 am, garage open and just headers on engine
Runs good, vanos spot on and no surprises.
So this was not smooth sailing at all!
Engine builder was not totally on board on the excessive parts cleaning to begin with but as the engine started taking shape so clean and nice, he was jumping to the sandblasting cabinet once in a while to bling parts ??
It is such joy to work with people that know exactly what they are doing, he as assembled approx. 100 S62 engines and is quite quick & resourceful. When he assembled my engine last time back in 2006 he started on a Wednesday with a bare block and the car was driving on Friday. We were much longer now with cleaning parts, installing things in the engine bay after engine bay respray and tuning all kinds of cars in between.
Now last night I put a new battery in and it started for the first time without help
https://www.youtube.com/watch?v=pRKGaZRnxdE
Now I will assemble the rest of the car, clean & paint everything as needed and drive next year. If needed we will fine tune the map when the engine builder returns next spring.
We started assembly the Monday before with the bare block and there were a few WTF moments that could have gone worse....
First was when we were gapping rings and connecting rods to pistons. I had laid it all out nice on the table ready for install. "Where are the wrist pin clips" asked the engine builder. We searched the table and found none. Luckily I had not thrown the box the pistons shipped in and the box was still laying behind the sandblasting cabinet. With the clips inside!! Luckily I had not thrown the box away. Bear in mind I´m in the middle of the Atlantic and everything takes ages to ship here
Next problem was that I just could not find the chain for the oil pump. Did not look good! I was checking part numbers in Realoem when I realized it was the same chain as in the heads between the cams. So we raided one of the old heads and got a chain.
Now we were in the final stretch the night before the engine builder flew back to Denmark. Engine went in during the evening and we calibrated the throttle bodies. Then we found out the new starter was dead. Did not work.... damn. But with a little debugging it became clear it was the earth wire for the engine was not getting good enough contact on the body side. Quick fix, phew.
After the starter was cooperating it quickly became evident that the old battery was not up to starting. We connected my trusty VW Caravelle to the terminal in front (did not work trying to charge/start by connecting to the battery) but it was just not powerful enough to crank (70 Ah vs. 110 Ah) so the engine builder helped by turning the crank with a wrench while I started.
No go, would not start. Then we found out the ECU was not getting a signal from the crank sensor. Then and there, 1:30 am, I remembered we had broken the crank sensor when taking the gearbox off many many months before. And had not ordered a new one. f
k.But believe it or not, we found one on a shelf in my garage from an order back in 2016. Replaced the sensor (that was a b
h to get out, was somehow almost fused stuck) and bingo, started just before 3 am, garage open and just headers on engine Runs good, vanos spot on and no surprises.
So this was not smooth sailing at all!
Engine builder was not totally on board on the excessive parts cleaning to begin with but as the engine started taking shape so clean and nice, he was jumping to the sandblasting cabinet once in a while to bling parts ??
It is such joy to work with people that know exactly what they are doing, he as assembled approx. 100 S62 engines and is quite quick & resourceful. When he assembled my engine last time back in 2006 he started on a Wednesday with a bare block and the car was driving on Friday. We were much longer now with cleaning parts, installing things in the engine bay after engine bay respray and tuning all kinds of cars in between.
Now last night I put a new battery in and it started for the first time without help
https://www.youtube.com/watch?v=pRKGaZRnxdE
Now I will assemble the rest of the car, clean & paint everything as needed and drive next year. If needed we will fine tune the map when the engine builder returns next spring.
Sf_Manta said:
Excellent choice of suspension 
look forwards to seeing some video of the finished car.
Just had my E46 overhauled engine wise but it's nowhere near the power of this monster. Still pleased with the results currently.
Yes this suspension is great, have had my old set since 2006 look forwards to seeing some video of the finished car. Just had my E46 overhauled engine wise but it's nowhere near the power of this monster. Still pleased with the results currently.
Some work done on the M5 over Easter. Got a couple of mates over, one of them a mech, the other just an engineer like me.
I had prepped the front wheel turrets, removed some surface rust, put some primer and paint on.
Plan was to install the new coilovers at the front and rest of the front suspension. We did that and some more. Just to make mech Markus annoyed, I put an aftermarket oil plug into the oil pan before we closed the motor. He is a firm believer in OEM parts only.
We also used the opportunity to examine the oil filter to see if the first startups on the rebuilt motor had left some surprises there. We didn´t find anything to worry about.
Markus the mech liked the new KWv3's
But absolutely did not like the old stuff we needed to seperate, some choice words in Icelandic were said.....
We did even manage to start on the rear coilover install but we soon saw that more maintenance was needed. So we plan on dropping the subframe and refresh all bushings and also brakelines that are too rusty. So now I have to make yet another massive order at Schmiedmann and we will continue as soon as that stuff arrives.
Always fun to work with people that know what they are doing - Markus mech was like a general ordering us engineers around. We made ourselves useful as assistants and general helpers
I had prepped the front wheel turrets, removed some surface rust, put some primer and paint on.
Plan was to install the new coilovers at the front and rest of the front suspension. We did that and some more. Just to make mech Markus annoyed, I put an aftermarket oil plug into the oil pan before we closed the motor. He is a firm believer in OEM parts only.
We also used the opportunity to examine the oil filter to see if the first startups on the rebuilt motor had left some surprises there. We didn´t find anything to worry about.
Markus the mech liked the new KWv3's
But absolutely did not like the old stuff we needed to seperate, some choice words in Icelandic were said.....
We did even manage to start on the rear coilover install but we soon saw that more maintenance was needed. So we plan on dropping the subframe and refresh all bushings and also brakelines that are too rusty. So now I have to make yet another massive order at Schmiedmann and we will continue as soon as that stuff arrives.
Always fun to work with people that know what they are doing - Markus mech was like a general ordering us engineers around. We made ourselves useful as assistants and general helpers
Fun continues, refurbing some parts on the front end, replacing others. Some rust from driving the car year round here in Iceland for ca. 10 years..... they do salt the roads.
Paint peeling of the SC oil coolers and the bracket and bolts for it had rusted badly.
Media blasted and will be painted.
Some surface rust on the oil cooler lines.
Media blasted and will paint.
New hood latches.
Bracket cleaned, new AC condenser.
Latches in place, much better.
This will not do.
Better like this.
New fan.
Almost complete.
Paint peeling of the SC oil coolers and the bracket and bolts for it had rusted badly.
Media blasted and will be painted.
Some surface rust on the oil cooler lines.
Media blasted and will paint.
New hood latches.
Bracket cleaned, new AC condenser.
Latches in place, much better.
This will not do.
Better like this.
New fan.
Almost complete.
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