Bowen Island Paint Job

[hanleyclifford]

At this point the most important thing to consider is the condition of the threads in the block. You have already opened the hole up to 7/16" and the stud will not hold. There is no harm in chasing the threads with the 7/16" tap but I don't think the prospects are good in light of what you have already posted. You may now be looking at a situation where the traditional helicoil is the only alternative which means pulling the head. Don't worry about that small water pump leak until the thread issue is resolved.

[ILikeRust]

You think some people are anal retentive about their Atomic 4 engines? You should see some of the guys over on the Miata forum!

There's a guy who posted a whole big long story about taking his engine apart, including going so far as to disassemble his HLAs (which most people don't do) to get the gunk cleaned out of them - complete with pics and digital calipers and explanations and everything.

The big difference between the Miata and the Atomic 4 (besides the obvious) is that there TONS of aftermarket kits and mods out there for the Miata from several vendors - lots to make them bump out a little more h.p., or a boat load more h.p. There are bolt-on turbochargers and bolt-on superchargers. You can take the stock 1.6L (early) or 1.8L (later) engines that originally were factory stock at about 110 hp and get 200 or more hp out of them.

And then there are the guys who swap out the little 16V 4-banger for a Ford 302 - or even a Ford factory crate motor - or - the ultimate - a Flyin' Miata crate motor, which can be tuned to pump out over 400 hp! In a car that weighs only about 2200 lbs. And yet it supposedly stays remarkably streetable.

Anyhow, to avoid further thread drift...

The procedure for the ATF flush is basically two oil changes in a row, but the first one is a bit different. The procedure is to first drain as much of the old oil out as possible and remove the old filter. Then put a cheap oil filter on the engine and pour in 1 qt of 50W oil and 3 quarts of ATF. Then let it just run at idle for about an hour or two.

Then drain it all out as much as possible and remove the cheap filter. At this point, some people reported that while the drain plug is off, they would run about a gallon of kerosene through the engine to flush it out good, but I don't know - I didn't do that.

Then, once you've got it good and drained, you put your good oil filter on the engine and fill with your favorite oil.

TO BE CLEAR: I am not saying anyone should do this with their Atomic 4 - it is a procedure suggested for old Mazda Miata engines to deal with crudded-up oil passages in the HLAs. It's relatively well-known on the Miata forum and lots of people (including me) have done it and report very good restuls. I'm just theorizing it might maybe could possibly maybe help in the A4 with something like stuck rings. I also suppose it might could help slow/lazy/sticking valves, too - even though we have solid lifters, if the valve guides or lifters get sticky, this should de-gummify the works and help things move more smoothly.

I don't need to do it on my engine, so I'm not volunteering my engine to be the test subject, but it's an interesting idear to consider for an engine that might could benefit from it... maybe?

[Marty Levenson]

re-tap?

Unfortunately I gotta plan ahead: short short sailing season here. Not that a dripping water pump would stop me going sailing, but if I have to order more parts for the stud problem I'll want to order anything for the water pump at the same time. The shipping costs are killers...the more at once the better.

I'll likely give re-tapping/chasing a try on Friday...off to work in Vancouver for a couple days...and hopefully sneak in a little time working on the wiring.

If re-tapping fails - and I do agree it is a long shot - off with her head!

Thanks again.

[edwardc]

...If re-tapping fails - and I do agree it is a long shot - off with her head!...

If you do have to pull the head and put in an insert, be sure to use a "repair bushing" threaded insert instead of a helicoil. Helicoils have a tendency to leak, and this hole goes all the way through into the water jacket. I know this one from experience with my first A4. The repair bushings, like the one MMI sells (OBLK_09_114), are solid-walled, whereas helicoils are not.

[Marty Levenson]

head off

Decided to take the head off to try re-tapping that stripped stud. Just wanted to have a good look. "Chased" the 7/16" hole with a tap, and now the stud screws in pretty well, but with two problems: it is a little wobbly (though straight) and doesn't seat (I can screw it down several turns below the block face).

Two questions:
1. With the head off, I am thinking I might get away with screwing in the stud to the proper depth, even though it doesn't seat. Is that a no-no?
2. I have read and heard many opinions on sealants. Ken and a bunch of local mechanics state that I should use Red Loctite. The retapping kit, and Don's pdf say to use JB Weld. Many on the forum prefer #2 Permatex.

I am leaning toward Loctite, might be strongest, but wonder if JB Weld will hold the "wobble" and seal better.

Please advise!

[Marty Levenson]

testing torque without the head

I'm wondering if there is a way to test a stud's holding power without putting the head back on. Put a short piece of pipe over it with a nut and washer on top, and torque it down....?

[ILikeRust]

Just my 2c - I do not claim to be an ex-spurt on the potential pros and cons of using one of those miracle goops over another, but if it were me and I were doing it, I feel that I would go with J-B Weld. I would get everything very good and clean with solvent to be sure all surfaces are completely free from grease or oil first.

I J-B Welded in my exhaust manifold studs - it's amazing stuff.

[Marty Levenson]

locktite vs JB

Thanks, Rust. Still pondering. My impression is that locktite is stronger, but maybe not as good at filling gaps as JB Weld?

Had a crazy inspiration. After gluing: as the stud is on the edge (exhaust manifold side), I could drill a pin hole (perpendicular to the stud) from the outside of the block, through the stud, and back into the block and pound in a steel pin (1/16"?) to keep the stud from turning. Not going there, but just thinking....

[ILikeRust]

Thanks, Rust. Still pondering. My impression is that locktite is stronger, but maybe not as good at filling gaps as JB Weld?

I seriously doubt Loctite is "stronger" than JB Weld. But I would agree that it does not have the gap-filling ability that JB Weld does. JB Weld is pretty strong stuff. Loctite is more like a glue of sorts and works well for good mating surfaces (i.e., clean, well-fitting threads). JB Weld is an epoxy that turns into a very hard solid when properly mixed and fully cured.

Had a crazy inspiration. After gluing: as the stud is on the edge (exhaust manifold side), I could drill a pin hole (perpendicular to the stud) from the outside of the block, through the stud, and back into the block and pound in a steel pin (1/16"?) to keep the stud from turning. Not going there, but just thinking....

I sure wouldn't go there. If the hole is so shot that even JB Weld won't hold it, then I would start looking at other cures - threading in an insert, or possibly having a shop do cast iron spray deposit welding to fill it in and then grind the surface flat, re-drill and tap a new hole.

[Marty Levenson]

a new problem!

Seriously cleaned the holes with acetone and taps. JB Welded the re-tapped stud and reinstalled all the leaking studs (Perm #2) today. Fingers crossed: cold torque it tomorrow.

Noticed some water stain around a water jacket side plate hole and tried to tighten it up...stripped! As were three others. Puzzled how something just goes from "hand tight" to stripped by itself....can the heat change do that? As soon as I turned the bolt I could feel it was gone.

Can I drill and tap these? The metal all looks good. I see on the forum people usually use the Moyer two hole repair kit. I understand that if the wall were in bad shape that would solve the problem, but is it advisable to drill and tap instead if the metal is solid? Drill 1/4" and tap to 5/16'"? Coarse or fine?

Amazed at the parade of problems!

Thanks!

[sastanley]

JB weld studs into the block!

Marty, I have two of my eight side plate holes oversized. Last year, I went to studs and ditched the bolts. I JB welded my studs in place. The P.O. had already torn up the 2nd from bottom left hole with the alternator support, and it was a 3/8" bolt. There was enough corrosion that I had to do the same to the bottom left hole...so I have six 5/16" studs and two 3/8" studs.

So, when I pulled all the bolts, I cleaned up the threads with a thread chaser, and then JB welded studs (two 3/8" & six 5/ 16") into all eight holes. If they are sloppy, there can be an issue with aligning the studs to fit in the side plate holes, so be careful.

With a little bit of work, I got mine to hold. I am using brass nuts & washers...kinda as sacrificial I figure...they are pretty cheap to replace. This spring, I am planning to replace the forward stbd drain hole (a little forward of the side plate, near the starter) with a zinc, similar to what Moyer Marine is doing with their blocks these days. That might keep the brass nuts from degrading.

The other option is to buy the stud repair kit that Moyer sells for the sideplate. That is my next course of action if/when these start seeping.

[Marty Levenson]

Good plan

Many thanks - I will get eight 5/16" x 1" studs tomorrow. I can use the four "good" holes with screws to align the JB Welded studs, then after those are set I'll switch around and do the other four.

I know there is an ongoing issue with the dissimilar metals, but as I am now fresh water cooled I think it will be manageable. I plan to use SS studs with brass washers and SS nuts. On our old A4, even with RWC, the SS bolts showed no sign of a problem after 12 years...they unscrewed easily.

Will use Aviation Permatex again on the gasket, washers and studs' threads.

Good to have a plan - thanks, Sastanley!

[Marty Levenson]

trouble uploading photos

Yesterday and today I was unable to upload photos. As a test I tried to upload photos previously uploaded....no luck. Is there a forum problem, or just me doing something wrong...?

[Carl-T705]

I'm not trying to discourage you here, but if you are not confident the your head studs can stand a backing off and removal of the head to make a proper repair to the damage head stud hole where is your confidence level on retorqing the head studs once the engine is totally assembled and run? This would not be the time for a failure that could be addressed now, on the bench with everything nice and clean and dry.
I wouldn't make any type of a fixture to Test the strength of a glued in head stud, you risk pulling up a section of the block around the stud and the head gasket will never seal. That's one of the reasons there is a sequence to tightening head bolts.
You have a very nice looking engine that appears to have a lot of time and money invested in, it should last a very long time when completed,
PS Marty You are not using the right size drill bit for the size tap you are using, that may be part of your problem with the new threads working for you

[sastanley]

Marty, I had the same issue uploading pics..Hopefully a temporary glitch that Admin Bill fixed up.

FYI - I could not find SS studs the correct size/length, so I made my own. If I recall, I bought 3" bolts and chopped them in half with a Dremel tool, then chopped the heads off and filed the rough edges until I could get nuts on them easily. My thread chasing set helped with the burrs, although a die set would do the same.

P.S. Carl has a good point. Pull the head and fix the head stud issue while it is on the bench.

-Shawn