Blown head gasket? Video

[CarBuff]

NO RTV!!!!

 

You can use Loctite 5188 (formerly 518) for the cam towers to head surface. It is an anaerobic sealant. You don't need much thickness, literally just 'paint' it on with a brush. Some folks have used the Loctite primer, as well, but that reduces working time. How nimble are you?

 

 

My 5188 is holding up well after 4 years.

 

Regards the valve shims, don't forget that you need to fit the cam housings DRY then measure the gaps. You MAY need different shims.

 

I'd say don't mess with the carbon on piston tops.  That carbon provides extra compression! Plus, it looks about the same as mine look on the Borescope.

[Techspy]

Thanks Guys. Looks like I will have to start from scratch on the shims. Going to start reading the various posts on how to do it. Anyone know of a good video that shows the process? Anyone know of a good diy option for a head stand? Man, I was really hoping not to have to do this.

[Vulcan Grey]

Clean any previous thread sealant off all the bolts, otherwise they can strip the aluminum threads out of the head.

 

Use an Excel spreadsheet to measure and sort the shims.  but yeah it really sucks if they fall out like that and you have to do it several times (DRY no sealant!).  Add about .0005" for the final numbers to account for the sealant.

 

Doing it on a head on a bench is much easier than on an engine!

Don't clean the pistons, it'll drive grit down into the rings, where it is impossible to clean.

Don't skim the head unless absolutely positively necessary!  A machinist messed mine up and tapered it into a trapezoid, which made the cam belt try to walk off!

 

[Techspy]

Thanks Travis. Yeah, at least it will be on the bench for the shims. Not cleaning the pistons is the plan. Any preference on the cam tower sealant? Seems the Locktight 5188 is a bit more available around here. Oh, and did you use the angle method along with the ARP studs?

Edited March 19, 2018 by Techspy

[Vulcan Grey]

5188 or the older 518 if you can find it. 

I did not use the torque angle method. I struggled with finding the correct torque.

The Lotus spec change to the torque angle when they went to the taller composite gasket (Goetze) IIRC. I used one back in 2002 and that held up fine, but I think I used the old Lotus spec for torquing. 

Later I used the JAE black gasket and added the ARP studs with fine pitch. That lasted ~6k miles and blew at #4 on the track after losing over a gallon of coolant due to a bad pressure cap on the overflow. I think I torqued that to the old Lotus spec as well.

Then I replaced that with another black gasket, and that lasted exactly 1/2 of a day. I torqued that to the newer spec for the ARB fine pitch studs, which was 100ft-lbf ARP Ultra Torque lube (from Jeff at JAE). But I think that one died due to an overheat due to poor coolant flow out of the back of the head, which was due to a sensor that I had added to measure coolant temp out of the head...

[Techspy]

Good info. Just spoke to Joe at JAE and he said no angle method needed and that the studs are basically hand tight into the head and incremented to 110 for the nuts. I will get some 5188 ordered.

Edit: Wow, 518 available on amazon next day delivery. Ordered.

Edited March 19, 2018 by Techspy

[Vulcan Grey]

Do make sure your head studs are fully seated in the bottom of the bore, (hand tight, do not torque). See below.

http://arp-bolts.com/p/FAQ.php

Quote

Do the head studs only go in hand, or finger tight?

Yes, cylinder head studs are installed only hand tight. Other than the use of an allen wrench on the hex broached into the end of the stud (to ease installation, not to apply torque), use no tools to seat them in the block. However, it is extremely important to ensure that the studs are fully bottomed out in the hole in the block and not hung up on damaged or corroded threads in the block preventing the stud from being fully seated. This is often indicated when the stud threads extend past the deck surface.

 

The reason is that you want the stud to be bottomed out and unable to turn more when torque is applied to the nut. If they weren't then it is possible to strip the block.

 

[Techspy]

Thanks for that!

Looks like I will be following the info in this thread;

http://www.lotustalk.com/forums/f164/valve-shim-setting-help-166785/

Going to build a head stand/fixture now.

[Techspy]

Intake shims are done and all are between .005 and .007 except one that is .009. As I understand it the measurement gets tighter as it wears. Should I be concerned about the .009? Exhaust is next which will be a lot more trial and error. Got the intake done in 2 attempts.

Thanks.

[CarBuff]

I would investigate or adjust the one that is .009.  (Is there a worn spot in one of the shims on that valve position?  It could have been OK if initially measured on the worn area.)

 

In my experience, the intakes can be adjusted to the specified clearance range.  The exhausts (which are MORE prone to tightening) should be purposely set to the loose side of spec.  (That's what I do on my Hondas and my Esprit, anyway.).

[Tocus]

i really enjoy your Youtube movies about removing the Cylinderhead,

i have done it a lot before, but i always take the engine out, (only because then i have space all around the engine)

and it works faster then with the engine in....

 

please also make a movie when you build it up again, its nice to see a "newby" working on a 910 engine!

[Techspy]

Boy I screwed that up (don't ask). I will be ordering shims tomorrow. I have 9 total (intake and exhaust) that are just out of spec. I was able to swap 4 (2 on the intake and 2 on the exhaust).

Yep, I plan on a video per day of working on this until it is back on the road. Fingers crossed I will be done by the weekend. Would have been sooner if I didn't have to order shims.

 

[Tocus]

7 hours ago, Techspy said:

Boy I screwed that up (don't ask). I will be ordering shims tomorrow. I have 9 total (intake and exhaust) that are just out of spec. I was able to swap 4 (2 on the intake and 2 on the exhaust).

Yep, I plan on a video per day of working on this until it is back on the road. Fingers crossed I will be done by the weekend. Would have been sooner if I didn't have to order shims.

 

Saab / Rover shims are the same, that ones i always order very cheap and easy to get

[Techspy]

Anyone have an online source for rover/saab or compatible shims?

All needed in stock and ordered from JAE.

Edited March 20, 2018 by Techspy

[Vulcan Grey]

keep in mind a little carbon grit can hold a valve open (increasing clearances). A little pop with a plastic mallet can pop open the valve enough to get it to seal better against the seat.

[Techspy]

53 minutes ago, Vulcan Grey said:

keep in mind a little carbon grit can hold a valve open (increasing clearances). A little pop with a plastic mallet can pop open the valve enough to get it to seal better against the seat.

Good info. Thanks

[Techspy]

While waiting on the shims I am gathering the coolant, oil etc for changing once back together. But, I am trying to decide on the best coolant. There are so many different opinions in various threads but most are kinda old. What do you guys run in your engine nowadays? Also, as far as flushing it really well, should I just fill with water and run for a few miles and then drain and add the proper coolant mix? As for oil, as long as it has been sitting, especially with the head off, I am planning on draining the oil before it goes back together and filling up once the head is back on (filter too).

Thoughts?

[Chillidoggy]

Blue coolant is the recommended, not the later red OAT.

As for oil, personally I use Mobil 1 10W/60, however you have a much wider selection of oils to use in the US than we do here. No doubt they’ll be other suggestions from other owners forthcoming, too. I do think it’s a wise move to change the oil and filter, and like they say, “oil is cheaper than engines”. Thanks for the posts and videos, really enjoy them, although it’s sad to see you’ve had the head gasket problem.

[Techspy]

Well I picked up some Zerex G40 that is described as pink in color. Is that what I should avoid?

https://hd.valvoline.com/our-products/zerex-g-40r

If so, can you provide more info on what you mean by "Blue coolant"? Do you mean this formula which comes in red or blue?

https://www.valvoline.com/our-products/antifreeze-products/zerex-asian-vehicle-antifreeze-coolant

More vids posted, just not spamming the thread here with them.

Thanks

[Techspy]

Nevermind, I swapped it for some G05 that seems to be recommended by Valvoline and other Esprit owners.

[Tocus]

John, i am now doing a lotus excel, cylinderhead rebuild.

i took the engine out this morning, and get the cylinderhead off

when i did that i was thinking back on your movie, hahaha wish you good luck with building up and set the valve´s right!

 

[snowrx]

Price and availability of the Valvoline VR-1 20W/50 oil are good, and it has the zinc compounds that are supposed to be good for our tappets.

 

[Techspy]

Thanks Guys. I use Mobile 1 15w50 and was more asking about the flush procedure after having oil and coolant mixed.

[Techspy]

Well apparently I have screwed something up. Got everything done today, set timing belt tension to around 94 hz. Seemed the same tension as before. Started, it stuttered and wouldn't run. Pulled plugs, had fuel. Checked plug wires=correct. Turned to TDC and found that the intake had jumped 2 or 3 teeth. Checked cylinder heads with my borescope, no signs of valve collision. Loosened belt, put intake cam back, tightened to about 120hz. I know that may be too high but I haven't been able to find a HZ setting for the gates belt. Figured if it whines it is too tight and I will adjust. Tried again. It runs but is very rough. To me it still sounds like timing but I confirmed all marks line up and are exactly like before I started the teardown. See picts. Does it look like I am off a tooth on both? Looking at the picture it kinda looks like the dots need to go up one tooth. Video shows how rough it sounds. With the plugs out and turning it with a wrench by the crank, everything feels smooth. Pretty low at the moment. I hope I didn't screw something up.

 

[910Esprit]

Looks OK to me but of course I dont have the perspective from photos.   Why not run a compression test to rule out mechanical damage?    You could also pull plug leads in order to see if you have an issue with a single cylinder?