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Discussion Starter · #81 · (Edited)
Captain,

For clarity, this part does eliminate the banjo fitting, replacing it with a fully open 10mm fitting on that end. Thanks for the reverse flow advice. I'll be manually pulsing it and I have two cans so I should get any dried crud out. Was planning to do it twice in the event the first pass only softens some and the second would further clean it.

On the threads, yeah they're damaged. It appears that the stud was only inserted perhaps 1/2 as far as it would maximally penetrate the threads in the head. Then the other end was tightened. Classic mistake - always screw a stud in to full depth before pulling on it is my mantra. So they've been partly pulled out. Bummer is the deeper threads are perfect. So if there were a threading tool that started in the bottom of a blind hole and came out, I'd be all set. I'm afraid the threads the tool will start with are out of synch with the good deeper threads, so I'll be pressing for all I"m worth hoping to get the tool to match them when it starts on the good ones. It's an M10 X 1.25 if anyone else is in this boat some day. Oddly my full set did not have this one, so I'm picking one up at NAPA.

PS - I cleaned the threads out with a dental pick but just as they rejoin the good threads deep in there, the thread is cracked and distressed. Before I start, I may conclude its best to drill out the bad threads, then install the stud into the remaining deep threads and use epoxy to fill the space for the drilled out threads. It's not rocket science and the other exhaust manifold threads are fine. Going to be a judgement call...
 

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Your best option on the threads will be a thread insert. Heli Coils are more than sufficient and will be stronger than the original threads. Napa will have an appropriate kit for this usually. The 1.25 thread pitch isn't very common outside of Japanese/Asian vehicles so it may be hit or miss.
 

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Discussion Starter · #83 ·
Yes - agree an insert would be excellent and if more than one were showing distress I'd make that happen. Fortunately, it's just one of eight studs, and I'll be cleaning them all and properly torquing with the engine in a stand, versus leaning down in the dark engine bay and potentially buggering another on install. I've never resorted to using these - a small miracle considering my little fleet of rescued cars!
 

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I have a rather extensive collection of Heli Coils these days. Despite what some would say, they are an excellent tool when it comes to thread repair, especially on torque bearing aluminum threads.

I'll even put them in new threads if I think there's a chance of problems in the future.
 

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Discussion Starter · #85 ·
I was able to repair the threads of the exhaust manifold just with a stud and some tapping fluid and a little patience. By shoving hard I felt the damaged threads and the fresh deeper threads match up and then i spent some time going back and forth and then got it to full depth. So all is well there.

Then on to the valve springs which measured within a tight range around the target in the factory manual. Now Im measuring the shims in prep for the valve adjustment. Can anyone point me to a good technique for doing the valve shim job? The main thing here is I've done a valve lap job, so the shims have no relevant home - start from scratch.

So how do I do that? I can't figure out how to start at a baseline other than installing the cams and then a random selection of shim placement? I have all the shims measured and labeled. Any thoughts other than random and start checking measurements?
 

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If you have your shims separated in the order of the valves they came off of you can use that as a starting point. While lapping the valves does remove material it's not nearly aggressive enough to throw your clearances so far out that you're better off starting fresh.

If you've already mixed the shims up, then buckle up and get ready for the long haul. With the right fixture you can measure the installed valve height and do some math to figure out a closer starting point, but without it you're just playing with measuring tools.

Another method is to install one cylinders worth of valves (springs, retainers and all), install the cam so that the lobes for that cylinder are pointing away from the valves (same position as checking clearances essentially), measure the distance between the valve tip and the cam lobe, then find a bucket and shim that gets you to your desired clearance. Sometimes this may even get you the right clearance the first try, but don't necessarily count on it. It's also important to keep in mind that you can only have the 2 valves for 1 cylinder installed when doing this. Installing a cam without the buckets and shims in place can damage the valves, springs, or cams if the lobe is in a position to where the lobe is contacting the valve or retainer.
 
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Discussion Starter · #87 ·
Hmm, bad assumption on my part. I figured the valve lapping would throw everything off such that starting from scratch would be necessary so just yesterday I cleaned all the proper cylinder references I'd put on with a sharpie a year ago and relabelled them with their thickness. Ah well. So here's my new plan which I saw in an excellent video by the Supra gal (I'll add her name later) and the skilled owner of a machine shop. Install the cam and all the valves and buckets without the springs. So now you can freely turn the cam to each cylinder, and shove each valve up manually to get a rough clearance. I'll use a single shim to measure all of them and identify the largest clearance valves (actually writing all down). Then install springs and start using the thickest shims to set these, likely ending up with perhaps a quarter able to properly set before I need a machine shop to tip a few thou off the remaining valve tips I'm sure I'll need to open things up due to the valve lapping which will tighten things dramatically.

Unless someone knows of a reasonable source for the shims? FYI I bought the special tool to compress the buckets and pull shims in and out with the cam installed.
 

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saw in an excellent video by the Supra gal (I'll add her name later)
Faye

Install the cam and all the valves and buckets without the springs.
As long as you can find a way to hold the valves closed with a decent amount of pressure that's a bit better than the method I use. Just remember that the buckets aren't always consistent in their thickness. Measure your buckets with a good micrometer before assuming they'll all be the same.

Unless someone knows of a reasonable source for the shims?
They're commonly used on some Honda and Triumph motorcycle motors. Some Yamahas too if I remember correctly. Search for 25mm Honda/Triumph valve shims and you'll probably be able to track some down at a decent price. You may also check with any local motorcycle service shops you may have and see if they do shim exchanges. The shop I used to work at would do it free of charge as long as the shims were in good condition and you weren't trying to trade for the sizes we were low on. Some shops might charge a bit for it or just try to sell you new shims though.

Whatever you do, don't pay more than $5 per shim. They're available cheaper elsewhere.
 

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Discussion Starter · #89 ·
Yep, Faye. A lot of excellent and deep technical content in her videos on YouTube for MarkIII owners. Thanks for the tip on possible trades.
 

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Discussion Starter · #90 ·
So I started some preliminary measurements this evening, planning to insert the cams, springs and fully assemble. A glint caught my eye in an oil passage of the camshaft, so I experimentally pushed the broken end of a qtip into it to get the bit out. Came out with 5 bits! Ack, I had not cleaned the camshaft oil galleries when I did the head. So I fired a can of 3M brake cleaner through the ports of both cams and got a drift of aluminum dust probably equivalent in volume to a quarter of a BB. It's the same crud I got out of other parts of the head - super fine silver dust.

Now, I filled my parts cleaning tub with hot solvent and have been stirring them about, tilting them from one end to another, and I see there's just a bit of sparkles in the bottom of the cleaning tub. Argh. Being an amateur, I guess this is how you learn. If I had assembled this after all my work on the cam journals, it would have flushed this crud into them on startup. Wouldn't have destroyed anything, but still - might have undone half my work in 5 minutes of running in an aluminum paste. I suspect this is how a lot of 7M cams are running of course - just slowly grinding things up when people run them hard with cold oil.

Hoping to get back on it later tonight...
 

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Discussion Starter · #91 ·
So, tonight's excuse is I got invited today to a winter campout 4 miles from the British Columbia border this weekend. It's going to be 5 degrees at night, so I had to check over the Vanagon as I insulated it for winter camping when I restored it. But the battery was dead, it needed an oil change, and the aftermarket oil pressure guage has been acting up. So I dealt with all that and just parked it - ready to be packed. Cams are dry and clean and ready for Round 2...
 

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Discussion Starter · #93 ·
Thanks, Connor116. I'm starting the assembly and it feels good.

OK, my brain hurts. I'm tackling the shim and bucket valve adjustment tonight. I just got done using my thinnest shim to measure the clearance of all the valves just to be sure I have a starting point and no issues were created with the valve grind tightening things up. Turns out this doesn't close things up as much as I thought it would as the clearances were in the range but tighter. So now I have a standard clearance for every one of the 24 valves. However the last, the very last valve had zero clearance. I thought I was tired, so I did it 3 times, then pulled the bucket off to see if something was stuck to the valve tip, etc. All good, so this must have been where the thinnest shim was.

Now I'll do a chart of all the clearances and all the shims and see how many of them I can do with the existing shims. Then I'm headed over to a buddy's shop to tip the valves to get the rest of them in range. Wow. That was a lot of measuring, plus measuring all 24 shims and labeling them. Into it now!
 

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That was a lot of measuring, plus measuring all 24 shims and labeling them. Into it now!
You should try a Ducati Desmo valvetrain. It'll make you appreciate, and even possible enjoy, the 7M valve adjustment. I now have all my spare shims labeled with the actual thickness so all I have to do is grab the one I need.

Turns out this doesn't close things up as much as I thought it would as the clearances were in the range but tighter.
Yep, pretty typical for a basic hand lap job. What type of clearances did you end up with?
 

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Discussion Starter · #95 ·
Yeah, a buddy has a Ducati and says it's a difficult one, including the crankshaft end play as well. Yeesh. So clearances on the exhaust side range from .125mm to .19mm with an outlier at .27mm. On the Intake side they range from .22mm to .30mm with an outlier that has 0 clearance. So I'll be tipping some valves and will have the shims for most of the valves.
 

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Discussion Starter · #96 ·
OK, back in the saddle here with a few weeks of anguish figuring out the shim valve adjustment with shim options very limited to the home hobbyist. Some shops who specialize in Toyota have a few, dealers have zero and want $17 each for them, and all the motorcycle shops that used to use the same shim laughed at me and showed me the new type motorcycles have used for 40 years now. They look the size of aspirin tablets where the 7M shims are larger than a quarter.

I found a kind machine shop owner who let me tip my valve stems to get all my clearances at exactly the center of the range, or a half thousandths tighter. I'm super pleased and with that behind me it's really just knuckle dragger reassembly of the engine remaining. Unfortunately I have a business trip tomorrow or I'd get on that. My family will be happy as spring is also here so I can remove the block and head and temporary table in the spare room and do the rest out in the garage. Finally!
 

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I subscribed awhile ago and have a tendency to read more than I say. Can’t wait until you finish the knuckle dragging! I’ve slacked off back to simple tasks for the time being. I can’t really work more than say 15 mins at a time on anything really since this neck surgery, but I can still read about what everyone else is doing and live vicariously through @IdahoDoug
 

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all the motorcycle shops that used to use the same shim laughed at me and showed me the new type motorcycles have used for 40 years now. They look the size of aspirin tablets where the 7M shims are larger than a quarter.
Triumph is your friend here. Think I posted the list in your thread on the shims. They have some pretty recent models that still use the pancake sized 25mm shims still.

found a kind machine shop owner who let me tip my valve stems to get all my clearances at exactly the center of the range, or a half thousandths tighter.


My family will be happy as spring is also here so I can remove the block and head and temporary table in the spare room and do the rest out in the garage.
The real, appropriate course of action here is to move the whole car into the spare room. Once you've worked on a car on top of carpet, you never go back.
 

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Discussion Starter · #99 · (Edited)
So funny. Sitting in my Newark, NJ hotel room snickering about working on carpet. What sounds equally enticing is opening the garage doors and working out there as a gorgeous N. Idaho spring arrives. Ah, the smells of tulips blooming mixed with gear oil and my coveralls soaked with 10 years of various automotive chemicals - whats better!!

Pham, I'll start posting more pictures to keep you engaged and fired up. Nobody cares about a greasy old engine on the disassemble side of a project, but now it's clean things going back together, so more photo-friendly from here on out!

On a side note, that was wild using a valve tipping tool. You walk back to the head with misgivings each time. Did I take too much off? How many thicker shims are left in the head if I did? Cool, scary, then cool again...

Captain - I'll PM my wife's number so you can explain while I'm in NJ why there's a crew in the garage installing forest green broadloom carpet....
 

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Triumph is your friend here. Think I posted the list in your thread on the shims. They have some pretty recent models that still use the pancake sized 25mm shims still.





The real, appropriate course of action here is to move the whole car into the spare room. Once you've worked on a car on top of carpet, you never go back.
I have a tray that currently has about 50-60 shims. The plan is to pass it around for members of the San Diego group. The JZ uses a different size and they are the prominent engine it seems, but others have vowed to donate shims as they become available :). I got the cost down to a little over six bucks. I hadn't thought of Triumph. That's good info. Thanks.

EDIT: Correct that :) 24 of them go in my 7m
 
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