Esprit Turbo project car - part3 - the further continuation

[Chillidoggy]

1 hour ago, Lotusfab said:

My question now is could this scoring be cause be caused just by lack of oil? Im not sure but it seems like contamination. The oil test is not conclusive as it only  detects very small particles, much smaller thatn the glass bead. The sample came from the sump which was checked with the microscope. I should have saved some of the cam oil and tested that as well or got a microscope! 

The good news is with no sump contamination Imdontbhave to throw away the new oil cooler pipes and the rebuild will be easier.

 

Yes, it’s lack of oil.

[Lotusfab]

Thanks chaps, Barrys picture link is quite convincing. 

Theory One

The intial start , with the PRV stuck open and no oil pressure, must have caused excessive wear. This resulted in wear particles in the oil system. These then caused the deep scoring.

Theory Two

The iron cam follower started to break up releasing partcles into the system. The engine ran like this for sone time. These paticles started to score and cause damage. The engine stoped when the cam follower completly failed. 

Im almost ready to test the old pump ouput against a new one. I have removed the sandwich plate and bolted the filter directly on. Its refilled with new oil. I have a drill to power the pump. Once this is complete I will take the sump off and insect the bottom end. I expect to find the same scoring. If there isnt any I'll have to rethink. If this was all caused by the PRV and oil pump Ill be very pleased. A simple omission on my part (oil pump PRV) check,which isnt in the Turbo version of the manual,  will have caused this with the rest of the rebuild all good! 

Anyhow this time I am going to build a much better engine. I plan on balancing the crank with the flywheel and clutch. Should help out with the high rpm dyno testing!

Any other theories  out there?

[Sparky]

Yeah, the butler did it.

Seriously though, were it mine, I'd have the entire thing apart to help me figure out what really happened rather than spending ages on theories and suppositions.  But I get the feeling you secretly enjoy all this slow-burn detective back-and-forth.

And anyway, it's oil starvation, exacerbated by running the engine when that was already a known factor.  You knew that from the get-go!

[Lotusfab]

Should be all apart by the end of tomorrow.

Then, cleaning, mesuring and rebuilding.

[Sparky]

But with the evident damage to the top end, it's more than that, isn't it?  You're going to need to source/engineer a lot of stuff.

[Lotusfab]

Yep, unfortunately is going to mean a very big bill!

Replacement camshafts and maybe both towers( exhaust tower might be ok)

cylinder head new valves, guides, seats

Maybe new pistons and liners, conrods.

Crankshaft, might need regirding, balancng and new bearings.

all new seals

ouch! 

 

Have already sourced all of the parts needed to rebuild.

But even after that all Im still cost even over paying for a proffesional rebuild! Plus I will have effectively a new engine! 

Has anyone used new 107 QED camshafts? Just wondering how they comoqrevto the originals.

[Lotusfab]

Add an oil pump to that, its completely shot! 

[Lotusfab]

Thanks Dave(Lotusman)

Awesome test rig. Wouldnt fit on my turbo inlet manifold, but I just happend to have a spare S1 manifold. After testing the pump jet operation I would never bolt any rebuilt carbs in a car without calibration. One carb had no output! After adjusting I found myself screwing the adjusting screw way up the thread. The pump jet spring has gone weak and needs replacing. The other side the spring is passing through the pump jet arm! New springs and it will be really easy to calibrate exactly. Thanks Dave!

[LOTUSMAN33]

Your welcome, I have used it twice now and with some patience you can get them spot on.

Look forward to the results 😁👍🏻

Dave  

[Barrykearley]

5 hours ago, Lotusfab said:

Add an oil pump to that, its completely shot! 

And there’s the culprit. Onwards and upwards chap - love the carb test rig

[drdoom]

Fabian, your experience with the carbs serves to illustrate how older components may become unreliable, with predictable issues following on. Instructive to us all.

As to the engine matters advice remains to be contemplative over presumptive. I'm with @Sparky in getting right to the bottom of this mystery. Items like the cams are not necessarily in need of replacement if scored only on the journal surfaces as light polishing will ensure a bearing friendly surface without material change of dimension. I will always defer to someone with abundant experience, @Changes for example, in making such a call however. Con rods to be replaced?

[Lotusfab]

I am busy prepairing Andys auxillery housing and pump which will be used. Im thinking ifbreplaceingbthe rotor and annulus with new. Has anyone used the new ones, there are a few adverse stories? 

No sure how much will need replacing yet, early days. I have to measure everything again.

[drdoom]

Oil pump measurements are straightforward, no voodoo required.😀

[Lotusfab]

Yep, I'm replacing the rotor and annulus with new. I also have a replacement auxillery housing and oil pump housing thanks to Andy on here and its in very good condition compqred with the existing one. 

Im lucky and  have four micrometers and all the other kit needed to measure all of the components on the engine. As far as the cam housings I really need new camshafts so I can measure the housing to cam clearance and determine whether honing is practicle. 

Ill take the bottom apart tomorrow. Im really not looking forward to that! 

[drdoom]

I'm not sure that honing is in order here. There are no bearing inserts for the cams so going up on bore size is not to be done. As i have heard, the process for addressing embedded particle in these is to take a fine edged blade to the bores and judiciously scraping away any proud material. Careful examination by sight and feel should render a suitable surface, it seems to me. Honing does not remove significant amount of material, so not necessarily to be avoided though I'd advise it best to scrape the particles out before running in the hone. Of course check dimensions with micrometer as well.

[Lotusfab]

Thanks. I may outsource this job.

[Lotusfab]

Just got the sump off. Shocking! Theres pariticles in there that must have cause the scoring. Whether they are blast bead, cam follower bits or a combination I dont know. I have never seen that in an engine especially a rebuilt one! 

I will have to think carefully how to proceed. I cant have this happen again. Now I have seen a good oil pump its obvious the one one there was worn. 

I cocked this up. I should have examined the oil pump more carefully and not started this engine without oil pressure hoping it would come up! If your reading this dont make my mistakes! 

I will have the crankshaft out by end of today. The oil report came back with nothing unusual, but dont forget it cant detect large particles, there were a lot of the in the sump. It was like a grinding paste! 

 

[LotuStuart]

Can you post a picture of that sump paste? It wont help ME to identify it, but others here will have much more experience and might have a few ideas.

[Lotusfab]

I would have done but Ive already cleaned it! It just looked like a darl grey sludge. Maybe graphongen mixed in from the rebuild. And this was after the rebuild. My gut tell me blasting media and metal in there. Heres the Oil analysis as promised.They told me the Boron is probably due to oil additives. So no concerns from this report. Have to remember though where the sample came from and it only detects small particles.

[Lotusfab]

To be clear though I was getting 75 PSI from the pump at start, when I sorted the PRV. There must have been a lot of damage in a very short time span. 

[Fridge]

24 minutes ago, Lotusfab said:

To be clear though I was getting 75 PSI from the pump at start, when I sorted the PRV. There must have been a lot of damage in a very short time span. 

Surely, that damage couldn't have been that severe at that time? Otherwise you would have heard it during your testing?

How many miles and occasions had you driven it before the engine failed?

Also how many cold start cycles? Given that this is a crucial time for the running of any engine, particularly one which has just been rebuilt.

If this problem was largely due to the initial start up when you had poor oil pressure, surely you would have heard a progressive problem developing whilst idling (considering that's also when it failed) during successive tests? Yet this doesn't seem to have been the case.

Although the problem does appear to have been caused by the reasons mentioned by you and others previously, I'm not convinced it's the full picture. Exactly how much had this engine run before it failed?

Also, I know you had issues with your oil pressure gauge, but did not indicate a problem with the pump during this period? I'm still confused by all this TBH.

[910Esprit]

Just out of curiousity, what brand & type of oil were you using?   I'm not suggesting a connection, I'm just suprised that the viscosity has degraded so quickly due to shearing?   (I thought this happened over significant mileage due to the action of the cams breaking down the polymers in a multigrade oils).  

[Lotusfab]

Im not 100 percent on what caused this. The only hard evidence is the cam follower breaking up. The pump wear and the rest may have all been caused by this one thing.

Well the  bottom end is off. Pistons and bores appear ok, but need measuring. All bearings have scoring and must ve replaced. Big end journals need a regrind. A lot of cash!

Im not sure whether I want to rebuild thie again. The amount if effortand time I spent this should not have ocurred. Im asking myself if I should just go on holiday, get an expert to do it and come back to a new engine! That way if it goes the same way its their fault! 

Oh well Imhave a think about it!

[PhilW]

Fabian

I think youve been incredibly brave  taking the entire project on but equally youre abilities are something you should be very proud of.  You achieve more in a day than I achieve in 6 months sometimes. Occasionally however you do have to hold your hands up and say I need some assistance.  Ive learnt that to my cost in the past and sometimes you have to admit you cant do it all.  I would consider taking your wife away for a break but via PNM first myself.

[Sparky]

Seriously, Fabian, give it to PNM.  I'm not sure what the forum page limit is.