Esprit Turbo project car - part3 - the further continuation

[Lotusfab]

It was Mike at Lotus bits whi told me he has seen the same issue more than once.

[Lotusfab]

All of the tolerances on this engine were measured twice once by me and once by a professional. All the parts were examined for wear. The oil pump was checked and in spec. Every seal was replaced. There was nothing mechanically wrong. It fired up immediately but no oil pressure, as the valve was stuck open. That was just bad luck.  I took it off cleaned it and oil pressure!  Thre was oil in both cam towers the exahaut side almost competely submerged. 

Mike said had I powder coated the cam covers. I said no but then remembered a media blasting company had blasted them some years back. It explains whybthe engine ran for some months then failed as the components were being worn away. 

Its tempting to farm this out but I wont. I have built other engines and worked on cars and motorcycles for over 35 years and never had a problem until now. I will ensure all parts go into a sonic bath and start again with the plasti guage! As before I will get the professionals to confirm all my measurements. 

This time I will get Lotusbits  to test the engine on their rig before I put  it in the car.

I might get the oil analysed for blast media.

 

[Fridge]

I would get the oil analyised as a given, as it isn't too costly. This will tell you if there are any impurities, and ideally their composition and likely source. The last part being the most import bit!

If they don't I'd employ some sort of spectrum analysis. You did virtually the same with the paint colour, and this is more important.

I may have misunderstood, but if this engine has been run in the past with the powder coated components in place, then why wasn't this wear evident when you stripped it down?

Has the underside of the powdered coated parts (in the oil case) been completely removed in engine use, if it existed previously? If the coating remains and is intact, then where has the residual media come from?

As I said, I doubt that you've ran this car far given your recent completion, and unlikely to have stressed it, it being a new build. So, with the risk of repeating myself, I would remain objective as to the cause of this wear and catestrophic result. As I really do not think this is the cause.

If this problem is media related, then I would be checking the oil ways, as this is the more obvious route of the problem.

I always work on the principal that a problem is likely to be due to the most obvious cause. Occam's razor etc. That approach has rarely failed me.

[Lotusfab]

It hasnt be run for over 20 years. The top covers were media blasted both sides buy a powder coater,  but not powder coated. I cleaned them with brake cleaner. Then rattle can paint. The media can get imbedded and is released with hot oil. The cam towers and head were aquablasted as was the sump. The block was cleaned with compressed air, brake cleaner and pipe cleaners. All the oil ways were tripple checked, brake cleaner, pipes and compressed air. All the other aqua blasted parts were cleaned over and over with compressed air rags and brake cleaner, i would say I did more cleaning than most would. I really left no stone unturned. The wear can only be caused by lack of oil or abbrasive substance in the oil. Many rebuilds have been written off by blast media, which is why some garages wont use aqua blasting.

I found oil in both cam towers, the lower camshaft being submerged. I haven't yet got the lower cam tower off. When I do it will hold the answer. If its got the same wear, despite being immersed in oil, it must be due to media. If not then its an oil problem. All the oil ways so far are clear. 

I am planing a full spectral analysis of the oil which will,show up silicon content. Hopefully confirming what I suspect.

When I rebuild it again I shall replace the annulus, rotor and the housing. I shall also check the pick up pipe is not sucking air buy  putting a clear pipe on the oil cooler outlet and checking for air bubbles. 

Your correct I must be certain as to the cause. I hope people are learning from this it could save many many hours and a lot of money.

Im pleased all of my sealing has worked perfectly with no excess sealant so far. I will get the sump off and photograph! 

Was a shame to take the camshaft out. The rubber seals were perfect, as was the end float and cam snubber setting.  Im not goingbto flower this up Its gutting taking apart everthing that took so much effort to assemble. But, never mind these things happen. At least I have a stunning car which I will complete and put skis on!

[TAR]

So sorry to be reading about this problem knowing how much effort has gone into getting the car finished.

It's certainly made me consider carefully how I'll approach my engine rebuild. 

You clearly love the car and that'll help keep your spirits up.  🙂

[CHANGES]

2 hours ago, Lotusfab said:

All the oil ways were tripple checked, brake cleaner, pipes and compressed air.

 

2 hours ago, Lotusfab said:

I really left no stone unturned.

But you never removed the brass plug in the block giving access to oil ways .  This has an antechanber under it where media will gather and CAN NOT be removed with pipe cleaners and compressed air..  When aquablasting or media blasting you have to remove this to insure no contaminent get left there . !!!!!!!   ( You where informed of this and dismissed it saying your proffessional said it was not neccessary.. )   

2 hours ago, Lotusfab said:

The wear can only be caused by lack of oil or abbrasive substance in the oil.

I wonder where that came from..

2 hours ago, Lotusfab said:

I shall also check the pick up pipe is not sucking air buy  putting a clear pipe on the oil cooler outlet and checking for air bubbles.

  .. Do you really want to mess about with a piece of clear plastic pipe with oil at 80 psi...  good luck with that..  If you do the checks you were advised of , then fitted it  using correct torques etc etc,  you wont have issues in that area.   ( Was your pick up pipe knecked at the plastic olive point, ? did you check for it ? )

2 hours ago, Lotusfab said:

Your correct I must be certain as to the cause. I hope people are learning from this it could save many many hours and a lot of money.

   As far as the cam follower is concerned , it was burn't and worn like an old part, I expect it was shot to shit before it was fitted , if it had run without oil it would look very different and they would all be cracking ...

There is a reason these engines cost so much when built by proffesionals and it not just because of the cost of all the parts . 

good luck with what ever you choose to do ....  

 

[Barrykearley]

Cut open the oil filter and wash it out. You will find the media in there if it’s anywhere. If it’s in there - then you should scrap all your pipes and if you have oil coolers fitted - I’d scrap those as well.

this was the very reason all my plenum bits on all cars I’ve had done have never been blasted with media - it’s simply a nightmare to get rid of - as it lumps together in all the nooks and crannies and that’s on simple shapes - engine blocks and cylinder heads are horrendous to clean. Take a look at wheeler dealers TR6 - they had unleaded valve guide seats fitted - the head was placed in an auto parts washer system for something like 4 hours to ensure all swaft and machining debris was gone.

i do hope you can resolve and rebuild 👍

[drdoom]

In agreement with points made above I'd add that highly respected Lotus authority, Dave Bean, of California long ago wrote emphatic instructions never to go near engine parts in alloy with glass bead. He stated the beads would be lodged into the comparatively soft metal and then emerge in operation with the heat-cycled, oiled, and vibrating engine acting like its own ultrasonic cleaner. Sounds absolutely sensible to me, RIP DB who passed away just a year or two back.

Going on from here it's imperative to ascertain whether bead contaminants are found and to further examine other possible paths to failure, particularly in the valve gear. Oil of any decent spec is unlikely to be at the root of this in and of itself. Glass beads, if confirmed present, must be presumed still looming in any internal spaces where the associated alloy bits have been blasted. As Barry says, infernally difficult to clear away that. Scoring in the bearing surfaces of the cam towers is consistent with bead deposits and will, over time generate scoring on the iron cams if not somehow cleared away. Clear the surfaces, eliminate the systemic contamination somehow and the towers remain suitable for use.

Best of luck, keep us posted. 

To be accurate, not only glass beads will result in scoring in the towers as fragged steel particles in circulation have been shown to create the same markings.

[ChrisJ]

1 hour ago, CHANGES said:

There is a reason these engines cost so much when built by proffesionals and it not just because of the cost of all the parts

I've had two engines rebuilt by Gerald at GST - one Esprit, one Excel.  He took a couple of months each of them - both run  fine. I would do the same again if I had a third 9xx engine.

[Lotusfab]

8 hours ago, CHANGES said:

 

But you never removed the brass plug in the block giving access to oil ways .  This has an antechanber under it where media will gather and CAN NOT be removed with pipe cleaners and compressed air..  When aquablasting or media blasting you have to remove this to insure no contaminent get left there . !!!!!!!   ( You where informed of this and dismissed it saying your proffessional said it was not neccessary.. )   

I wonder where that came from..

  .. Do you really want to mess about with a piece of clear plastic pipe with oil at 80 psi...  good luck with that..  If you do the checks you were advised of , then fitted it  using correct torques etc etc,  you wont have issues in that area.   ( Was your pick up pipe knecked at the plastic olive point, ? did you check for it ? )

   As far as the cam follower is concerned , it was burn't and worn like an old part, I expect it was shot to shit before it was fitted , if it had run without oil it would look very different and they would all be cracking ...

There is a reason these engines cost so much when built by proffesionals and it not just because of the cost of all the parts . 

good luck with what ever you choose to do ....  

 

Hi Dave.

The block wasnt aqua blasted. Its was cleaned with brake cleaner. I put a boresvope into the oil ways . All were clear. I even took pictures of the internal oil ways.

My mistake was aqua blasting and media - never again! 

The plastic pipe method is used by other well known engine builders to check for air leaks on the pickup pipe.

I replaced the olive on the pick up pipe. Sofened in hot water prior to fit and torqued twice. 

There were no cracks visible in any of the followers. I didnt appreciate they were cast iron amd Lotus had changed them to steel . I understand now they have flaws which cant be seen. in hindsight I would replace all of them with the long skirt followers. I learned from that!

I was unlucky with this its not rocket science its just an engine. Im an enthusiast and even though I could farm it out I have built everything on this car. If I hadnt aqua blasted this and the oil pressure relief valve hadnt stuck I would have a perfectly serviceable engine. 

I agree though, if you do this all the time your would have built it quicker with less chance of problems, but would you have spotted the pressure refief valve issue before fitting? 

You've laid down the gaunlett now -  i will rebuild it again and it will be perfect! 

The other thing I have learned is I shoud have bench tested this engine prior to fitting in the car.

This time I will get Lotusbits to bench test it on their rig before it goes back in. I will post a video on youtube.

If it isnt perfect after this rebuild I will acknoledge you were right and have it professionally 

 

 

 

[Lotusfab]

8 hours ago, Barrykearley said:

Cut open the oil filter and wash it out. You will find the media in there if it’s anywhere. If it’s in there - then you should scrap all your pipes and if you have oil coolers fitted - I’d scrap those as well.

this was the very reason all my plenum bits on all cars I’ve had done have never been blasted with media - it’s simply a nightmare to get rid of - as it lumps together in all the nooks and crannies and that’s on simple shapes - engine blocks and cylinder heads are horrendous to clean. Take a look at wheeler dealers TR6 - they had unleaded valve guide seats fitted - the head was placed in an auto parts washer system for something like 4 hours to ensure all swaft and machining debris was gone.

i do hope you can resolve and rebuild 👍

Thanks Barry. Definately going to get the oil analysed. Filters a good idea. I dumped the oil and changed the oil filter after the first run to operating temp to ensure no glass bead. I should have put all parts in an ultrasonic ckeaner adter aquablasting. 

7 hours ago, drdoom said:

In agreement with points made above I'd add that highly respected Lotus authority, Dave Bean, of California long ago wrote emphatic instructions never to go near engine parts in alloy with glass bead. He stated the beads would be lodged into the comparatively soft metal and then emerge in operation with the heat-cycled, oiled, and vibrating engine acting like its own ultrasonic cleaner. Sounds absolutely sensible to me, RIP DB who passed away just a year or two back.

Going on from here it's imperative to ascertain whether bead contaminants are found and to further examine other possible paths to failure, particularly in the valve gear. Oil of any decent spec is unlikely to be at the root of this in and of itself. Glass beads, if confirmed present, must be presumed still looming in any internal spaces where the associated alloy bits have been blasted. As Barry says, infernally difficult to clear away that. Scoring in the bearing surfaces of the cam towers is consistent with bead deposits and will, over time generate scoring on the iron cams if not somehow cleared away. Clear the surfaces, eliminate the systemic contamination somehow and the towers remain suitable for use.

Best of luck, keep us posted. 

To be accurate, not only glass beads will result in scoring in the towers as fragged steel particles in circulation have been shown to create the same markings.

Yep I agree. Need to get confirmation from oil analysis.  I will have all parts ultansonic cleaned and some replaced. 

[Lotusfab]

http://www.millersoils.co.uk/services/oil-analysis

just sent out for this kit. It would be really useful to be able to compare results with someone who has a good engine. Anyone fancy getting their engine oil checked? 

I will post all details of the second rebuild on here. Except the sealants as that has been done on here and they all wroked perfectly. 

This will be a breakdown of how I recovered this engine.

[Sparky]

Let's all meet again on page 300.

[Lotusfab]

Might be more pages than that if theres another rebuild!

[Sparky]

And there's me thinking I was taking the piss.

[Lotusfab]

Incidently, S and J sports cars have recast the Exhaust manifold for the Tiurbo, great news if you need one!

[910Esprit]

What's everyone's view on 40 year old sodium cooled exhaust valves....?  

[Fridge]

I'm knicking that emoji.

[CHANGES]

3 hours ago, Lotusfab said:

The block wasnt aqua blasted. Its was cleaned with brake cleaner. I put a boresvope into the oil ways . All were clear. I even took pictures of the internal oil ways.

But not the antechamber I repeatably mention..   However lets just except there was no cleaning media or contaminants left in there ...  

3 hours ago, Lotusfab said:

My mistake was aqua blasting and media - never again! 

This was not a mistake ,  aqua or media blasting is not an issue and can provide a more effective and rapid cleaning service.   It does require and will need intensive follow up cleaning to leave no trace of media..  but done correctly with pressure washer and other methods it is not that much of a concern..      I honestly believe with the exception of the plug in the block and dowel pins in the head, from what you have said you will have cleaned all catchment areas to an exceptable standard . 

3 hours ago, Lotusfab said:

The plastic pipe method is used by other well known engine builders to check for air leaks on the pickup pipe.

I replaced the olive on the pick up pipe. Sofened in hot water prior to fit and torqued twice. 

  Point 1 ..,  Really ,   to check their own work , or look for problem on other peoples.. ?                                                                            Point 2 ..,  why soften it first..  this will change the torque dynamic..      But did you check for necking on the pipe , this can create issues.

3 hours ago, Lotusfab said:

There were no cracks visible in any of the followers. I didnt appreciate they were cast iron amd Lotus had changed them to steel . I understand now they have flaws which cant be seen. in hindsight I would replace all of them with the long skirt followers. I learned from that!

99% of cracks are invisible to the naked eye , which is why we crack test items..  However cam followers are usually showing some level of ware and old ones always show cracks, be they oh so slight , so it a no brainer just fit new ... at a couple of hundred quid Its cheaper than spending all the time fiddling and crack testing them ..  OR having to rip an engine out to rebuild because one shattered ....  To be honest the one in you pic looked as though it was pretty sick before being reused , so i think you are just going to have to own this one and move on.. 

How long are the skirts on your new followers going to be ?  what is the lift on your cam shafts ? will they end up bottoming out...  Always ask the reason why they were the length they were before you just change spec !!!!!!!

3 hours ago, Lotusfab said:

I was unlucky with this its not rocket science its just an engine. Im an enthusiast and even though I could farm it out I have built everything on this car. If I hadnt aqua blasted this and the oil pressure relief valve hadnt stuck I would have a perfectly serviceable engine.

Fitting sub standard worn parts is not bad luck..  It may not be rocket science but it also ain't  Lego..  Once again you seem to want to blame Aqua blasting, and also a stuck relief valve ...  You went into detail how you cleaned these parts , so how did it stick open .... It first had to open which mean you must of  had great oil pressure off the mark .. For dirt particals to get in the relief valve they would have only come from the sump , pick up pipe or auxilary housing gallery.  so unlikly as you fastidiously cleaned everything..   Also these relief valves to not have a habbit of sticking or there would be load of threads on them.  

3 hours ago, Lotusfab said:

I agree though, if you do this all the time your would have built it quicker with less chance of problems, but would you have spotted the pressure refief valve issue before fitting? 

 I doubt i would build any quicker , it actually can take several weeks and countless procedures and checks to complete a build , The manual is only a guide you can write volumes on what is not in it.  And yes i would have spotted any defect with the PRV, There is a test procedure to use prior to any fitting... 

4 hours ago, Lotusfab said:

The other thing I have learned is I shoud have bench tested this engine prior to fitting in the car.

Why ?  A bench test is just that , a start up test , you ran your engine for a while in the car showing the same symptoms as it would on a bench test, so where is the differences .  if a fault was apperent in inital running then you should have pulled it out and inspected..  if no fault at that initial start up , then you would have fitted and had the same situation you have..  I can not help feel you real over complicate an engine build many ametures have done without a fraction of the problems you have experienced.  ..  If you really want to do it right , put it on a  full dyno test run and tune ,  This will expose all issues you would experience under load ..    

 

[andydclements]

I've  had a 907 shatter a follower which then dug into the cam carrier and as Dave ( @CHANGES )  indicates they're not visible. What I did find afterwards is that they are audible, a crack makes the follower sound dull if VERY gently tapped like a bell. Thankfully mine cracked pretty much as soon as the engine started, so I actually saw the cam stop, at low revs. It was part of a low-cost rebuild of a then £1500 car & refurb (Lola for those that know that Excel), so not something I'd take the chance on for one of these engines as they now are getting a lot more rare and a lot more expensive to replace.

[Lotusfab]

Well the big picture here Is a professional engine rebuild could cost up to £10k. I can strip replace all of the parts as new and still have cash left over. But its not about the money. The whole point of this Is I want to build it all and i have done.

I admit to making mistakes we all do even experts, but now I have learned from them. It will be a simple matter to rebuild this again. Anyone reading this will be much more informed when they rebuild their engine.

Its annoying to have to take it all apart but Im almost at the point of engine removal after about 3 hrs work. This time the rebuild will be much  quicker. I have all of the equipment and have carefully bagged and listed all the parts.

I believe the pressure relief valve was open when the pump was fitted. Hands up  I didnt check it. Its not in the manual. I did diagnose the problem after the pressure failed to build. I took the housing iff and found it stuck open. This has been the cause iof other oil pressure problems in the past, as show in past threads on the forum . I had no idea of how long it should take to build oil pressure on aTurbo. I do now and have a new housing.

So these are the mistakes which which in my opinion caused this engine to have issues.

1. Should have replaced all cast iron cam follwers with steel.

2. Should not have aquablasted any of it.

3. Should have checked the oil pump pressure relief valve and replaced the annulus and rotor with new ones.

If I had done these things the engine would still be running perfectly. 

The actual assembly gaskets etc performed really well.  So not much to correct really. It may be possible the cam carriers can be recovered. If I cant find good used ones I will get an engineering company to have a look as repairing them. It might be possible to insert modern bearing surfaces to take the cam or resurface the orginals. 

I may only need one I still have to examine the other carrier which is still in situ. 

Hopefully someone has got some cam carriers for me.

My plan now is take apart everything. Sonic clean. Measure all tolerances. Replace anything out iof spec and reassemble. Then test rig. Why not put it straight back in the car. Well its a lot easier to check, dismantle, test,  adjust or replace parts when its out of the car. 

 

[Barrykearley]

@Lotusfab just one thought - you did disconnect the oil supply line to the turbo charger, crank the car over(not allowing a start so with plugs removed) and recover about 0.5l of oil?? I’m sure that’s the process before starting a later engine

[Lotusfab]

Hi Barry, thats a worry, No? I havnt heard on that before. Do you know why that is recommended?

[CHANGES]

It has been mentioned quite a few times in various threads  , but it is...To insure, ,,   1..   oil pick up and pump is primed before starting ,  2, pressure can be achieved and no leak back is present ie. open PRV !!!..  3,  to judge flow rate and asses system set up correct..  4.. When firing a shorttime later the oil pressure will be seen at the bearings before the assembly compound defuses.. 

 Its not in the book, just something some do,  ( experience )others like me use a pump to pressurise the system first, then fire..   The later gives a pressure reading which reflects all areas on a cold start..  If pressure low then something is not as it should be, then can vbe investigated before even turning the key..    This can also be done before the engine is even fitted to a car...  However if you do it on the stand you can wash out the assembly compound , depending on which one you use,  so will definatly need to do it in the car again before initial start up..   

[Barrykearley]

51 minutes ago, Lotusfab said:

Hi Barry, thats a worry, No? I havnt heard on that before. Do you know why that is recommended?

The oil pumps are awful and do not self prime if dry.

it could have caught me out on the S4s - but with the cash injected into mine and the new turbo it was worth the time and effort to check what some might ignore. The turbo supply line is the last pipe on the galleries until oil is returned to the sump. Priming that pump was a complete and utter pig and needed a decent pump to pump oil round the system backwards.

its one of the key issues to make sure you get correct on any engine - had I not checked - a few seconds of running would have added 10s of thousands of miles of wear to my engine