Tommu Engine Re-Re-Rebuild

Moderators: Sluggo, Amskeptic

Jivermo
IAC Addict!
Status: Offline

Tommu Engine Re-Re-Rebuild

Post by Jivermo » Fri Jun 29, 2018 3:10 pm

Any update on what’s up with the engine, Tommu? Are you going to tear it down...any idea what caused the slow down? I know how discouraging this is, as it reminded me of when Colin and I installed my newly rebuilt 2.0 in my ‘78, cranked it up, and it ran beautifully! And then...we noticed the constant oil stream flowing down from the (as we found) improperly installed gallery plug. The builder accepted responsibility, and redid the entire job, but, oh, my. Discouraging business. Silver lining is that I got real good at pulling and installing my engine.

User avatar
Amskeptic
IAC "Help Desk"
IAC "Help Desk"
Status: Offline

Re: Tommu Engine Re-Re-Rebuild

Post by Amskeptic » Fri Jun 29, 2018 7:13 pm

Jivermo wrote:
Fri Jun 29, 2018 3:10 pm
Any update on what’s up with the engine, Tommu?
Update, update, update! We'll wait right here.
ColinInLivingstonMT
BobD - 78 Bus . . . 112,660 miles
Chloe - 70 bus . . . 206,845 miles
Naranja - 77 Westy . . . 121,400 miles
Pluck - 1973 Squareback . . . . . . 55,570 miles
Alexus - 91 Lexus LS400 . . . 92,435 miles

User avatar
tommu
Old School!
Location: Sunny Burbank
Status: Offline

Re: Tommu Engine Re-Re-Rebuild

Post by tommu » Mon Jul 09, 2018 10:15 pm

Jivermo wrote:
Fri Jun 29, 2018 3:10 pm
Any update on what’s up with the engine, Tommu? Are you going to tear it down...any idea what caused the slow down? I know how discouraging this is, as it reminded me of when Colin and I installed my newly rebuilt 2.0 in my ‘78, cranked it up, and it ran beautifully! And then...we noticed the constant oil stream flowing down from the (as we found) improperly installed gallery plug. The builder accepted responsibility, and redid the entire job, but, oh, my. Discouraging business. Silver lining is that I got real good at pulling and installing my engine.
Thanks for asking Jivermo. I think we have an answer.

When I started splitting the case I found lots of grit clinging to lifters. With the heads off, any rotation of the crank caused a shocking crunching / grinding sound. I stripped the engine down more and found less grit - but evidence of grit everywhere. Scoring of the cylinders and what looked like scoring of the main bearings. I decided that the Pushrods, which had been glass beaded, released their hidden treasure when the oil was hot enough. I sent oil off for analysis and parts off to the machine shop. The oil analysis came back showing elevated silicone but not aluminium or other metals you’d expect from a engine cum gas powered sander.. What happened?

This Saturday I picked the parts up. It turns out that I’d been using STD bearings on a .25mm crank. So the lack of ability to build oil pressure from the starter, the knocking, the almost seizing and the weird tightening with the clutch engaged were all caused by loose bearing clearance. In fact only the Mains journals had been ground but not the rods.

RIMCO sold me the bearings. They pair up nicely with balanced rods they sold me which were only had 10 grams difference between them!

But blaming Rimco is an indulgence. I only measured the rod clearance and not the mains so I really am at fault. This adventure has taught me some hard lessons.

The worst thing of all is that there were no leaks whatsoever. That engine was oil tight and smooth!

I’m now getting ready for days of relentless case cleaning :-(

Lifter:

Image

Number 1
Image

Grit
Image

Jivermo
IAC Addict!
Status: Offline

Re: Tommu Engine Re-Re-Rebuild

Post by Jivermo » Mon Jul 09, 2018 11:17 pm

Oh, man, this is really tough to hear. Did you mean “silica” regarding the test of the oil, instead of “silicone”? The glass beads were the cause of the grit, is that right? My understanding of media blasting using glass is a no-no for any internal engine parts as the glass easily “hides” in crevice, indentations, oil passages, piston ring grooves, etc. Colin and I found some traces of some sort of grit in my valve covers in the rebuilt engine that had the oil gallery leak. He pointed out, at that time, that it was not a good sign of either the shops methods or cleanliness standards. I was very bummed out. As it turned out, I sent the engine back, and the replacement had no such contamination. A very laborious cleaning chore ahead, I’m sure, and I feel for you. Will you use soap and hot water, or some kind of chemical dip? Then the bearing size was the second cause of failure. I guess, either way, the engine was doomed. The photos are painful to see. Does this mean any other new parts, other than the bearings, of course, or are any of the other parts usable with some cleaning? Best of luck with your forthcoming rebuild, and thank you for sharing the causes, as the info may well benefit others from this sobering experience. I hope you’re back on the road soon.


User avatar
tommu
Old School!
Location: Sunny Burbank
Status: Offline

Re: Tommu Engine Re-Re-Rebuild

Post by tommu » Mon Jul 09, 2018 11:32 pm

Oh it's Silicon rather than silicone. The e makes quite difference :)

The bearings were the primary failure. The silicon grit would have got me if the bearings didn't first! I feel I came off lightly.

I have some very high foam car shampoo, wondering if that would help better than normal detergent. But yes. I'll be cleaning till Colin drives by in 2019.

User avatar
Bleyseng
IAC Addict!
Location: Seattle again
Contact:
Status: Offline

Re: Tommu Engine Re-Re-Rebuild

Post by Bleyseng » Tue Jul 10, 2018 5:58 am

Sorry to hear! Next time use plastic gauge to check the bearing clearances! Yes, it's a pain to do on the mains but worth it.
Geoff
77 Sage Green Westy- CS 2.0L-160,000 miles
70 Ghia vert, black, stock 1600SP,- 139,000 miles,
76 914 2.1L-Nepal Orange- 160,000+ miles
http://bleysengaway.blogspot.com/

User avatar
Amskeptic
IAC "Help Desk"
IAC "Help Desk"
Status: Offline

Re: Tommu Engine Re-Re-Rebuild

Post by Amskeptic » Tue Jul 10, 2018 7:14 am

tommu wrote:
Mon Jul 09, 2018 11:32 pm
I have some very high foam car shampoo, wondering if that would help better than normal detergent.

It is not about the foam. It is about the surfactants.
Nothing beats Dawn Dishwashing Liquid for cleaning little birds and contaminated little engines.
Colin
BobD - 78 Bus . . . 112,660 miles
Chloe - 70 bus . . . 206,845 miles
Naranja - 77 Westy . . . 121,400 miles
Pluck - 1973 Squareback . . . . . . 55,570 miles
Alexus - 91 Lexus LS400 . . . 92,435 miles

User avatar
Amskeptic
IAC "Help Desk"
IAC "Help Desk"
Status: Offline

Re: Tommu Engine Re-Re-Rebuild

Post by Amskeptic » Tue Jul 10, 2018 7:21 am

tommu wrote:
Mon Jul 09, 2018 10:15 pm
So the lack of ability to build oil pressure from the starter,
the knocking,
the almost seizing and the weird tightening with the clutch engaged
were all caused by loose bearing clearance.
In fact only the Mains journals had been ground but not the rods.
Not this one. This one was solely grit.
And you, tommu, do not get to select what the "primary failure" was.
I say "grit" is a thousand times more destructive a thousand times quicker, than mismatched bearings.
Like I mentioned in PM, I had a customer with 7,000 miles on his engine with std main bearings on a .010 crank.

I think RIMCO needs to explain to you why they only ground the mains and not the rods. (I would have done the same thing, by the way, because you already have small rod journals on 71mm cranks, but geeze, point it out!
Did they tell you? Was it scribed on the crank?
Colin
BobD - 78 Bus . . . 112,660 miles
Chloe - 70 bus . . . 206,845 miles
Naranja - 77 Westy . . . 121,400 miles
Pluck - 1973 Squareback . . . . . . 55,570 miles
Alexus - 91 Lexus LS400 . . . 92,435 miles

User avatar
tommu
Old School!
Location: Sunny Burbank
Status: Offline

Re: Tommu Engine Re-Re-Rebuild

Post by tommu » Tue Jul 10, 2018 8:21 am

Amskeptic wrote:
Tue Jul 10, 2018 7:21 am
tommu wrote:
Mon Jul 09, 2018 10:15 pm
So the lack of ability to build oil pressure from the starter,
the knocking,
the almost seizing and the weird tightening with the clutch engaged
were all caused by loose bearing clearance.
In fact only the Mains journals had been ground but not the rods.
Not this one. This one was solely grit.
And you, tommu, do not get to select what the "primary failure" was.
I say "grit" is a thousand times more destructive a thousand times quicker, than mismatched bearings.
Like I mentioned in PM, I had a customer with 7,000 miles on his engine with std main bearings on a .010 crank.

I think RIMCO needs to explain to you why they only ground the mains and not the rods. (I would have done the same thing, by the way, because you already have small rod journals on 71mm cranks, but geeze, point it out!
Did they tell you? Was it scribed on the crank?
Colin
I missed the point that your customer drove 7000 miles with those bearings. Kind of amazing they went that far.

RIMCO didn't actually grind my crank. Marine Crankshaft inspected it, polished it and were supposed to measure it. They told me it was 'fine'. I now know what follow up questions I should have asked them. I then dropped the crank at RIMCO to balance with the engine and asked them to sell me the correct main bearings. I know now I should have specifically asked them to measure the crank when selling me bearings for the case they had align bored.

Someone should write a step by step process for engaging with machine shops..

User avatar
Amskeptic
IAC "Help Desk"
IAC "Help Desk"
Status: Offline

Re: Tommu Engine Re-Re-Rebuild

Post by Amskeptic » Tue Jul 10, 2018 4:57 pm

tommu wrote:
Tue Jul 10, 2018 8:21 am
A) I dropped the crank at RIMCO to balance with the engine and asked them to sell me the correct main bearings.

B) Someone should write a step by step process for engaging with machine shops..

a) Then it is categorically on them. They sold you the incorrect main bearings.

b) You know, that is a good idea . . . .
Colin
BobD - 78 Bus . . . 112,660 miles
Chloe - 70 bus . . . 206,845 miles
Naranja - 77 Westy . . . 121,400 miles
Pluck - 1973 Squareback . . . . . . 55,570 miles
Alexus - 91 Lexus LS400 . . . 92,435 miles

User avatar
tommu
Old School!
Location: Sunny Burbank
Status: Offline

Re: Tommu Engine Re-Re-Rebuild

Post by tommu » Sat Jul 14, 2018 11:41 am

This is a brass bore brush that snapped off at the thread of the adapter threads as I was pulling it out of the gallery while cleaning the case in detergent. The threads are just inside the gallery - too far down for a pair of pliers and too precarious for me to try anything brutal like an EZout.

Image

The case is currently with an Engineering Discharge Machining specialist for removal. The hope is they can spin of the threaded adapter from the brush and then use a new threaded rod to pull the brush out. The way this is all going.. we will see :shaking:

This is what you can see:
Image
And this what the brush itself looks like
Image

Jivermo
IAC Addict!
Status: Offline

Re: Tommu Engine Re-Re-Rebuild

Post by Jivermo » Sat Jul 14, 2018 12:39 pm

Oh, brother...what a nightmare this is. Can you get a small, very high quality new drill bit to lightly drill into that affair, and then work a small screw into the hole, to pull it out?

User avatar
tommu
Old School!
Location: Sunny Burbank
Status: Offline

Re: Tommu Engine Re-Re-Rebuild

Post by tommu » Sat Jul 14, 2018 4:26 pm

Jivermo wrote:
Sat Jul 14, 2018 12:39 pm
Oh, brother...what a nightmare this is. Can you get a small, very high quality new drill bit to lightly drill into that affair, and then work a small screw into the hole, to pull it out?
I thought about that and an EZout. I had already ground down the tips of some some small pliers to see if I could get some grip without touching the gallery. It's all such a tight fit and so delicate that I've taken it to somewhere that should be able to remove it for me. I hope. The perfect tool would be an 8/36 stud extractor slim enough to slip into the gallery. And I don't think they exist!

User avatar
tommu
Old School!
Location: Sunny Burbank
Status: Offline

Re: Tommu Engine Re-Re-Rebuild

Post by tommu » Sat Jul 14, 2018 4:32 pm

And here's the latest example of devastation that grit or glass bead can do to an engine:

Image

These are brand new Blueprint HAM heads. That's a gouge in the valve stem I can feel with by finger. It's been caused by grit trapped between the valve stem and the adjusted screw. I emailed Len for advice and he recommended lash caps. A sensible solution but it really sticks in the throat to need them on a new head. Am I being fussy if I think about paying for new valves? I need to take a close look at the screws too. I bought OEM VW adjusting screws and will be pissed if I need to replace them too.

The lesson here is not to let anyone bead blast your pushrods for you. Or anything else that goes near the inside your engine. It's devastating.

Post Reply