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engine mount thread holes cracked

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Old 10-01-09, 10:09 AM
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engine mount thread holes cracked

Starting from the left, count the tension bolt starting with 1, look at the end plate area for tension bolt #3 and tension bolt #4. Someone used too long an engine mount bolt and threaded too deep into the hole causing a portion to crack off and which they sealed with silicone sealer.




Here is a picture of a good one.





Here is the part that concerns me the most. Looking at the bottom of the engine towards the rear where one of the passenger side engine mount bolts up to. It looks like someone had too much silicone sealer into the bolt hole with too long an engine bolt.



Questions:

1. Any idea for why this occurred? installation error?
2. Any way of fixing this? Welding into a cast iron end plate would be a real bitch.
Old 10-01-09, 10:25 AM
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1. probably installation error

2. only dependable way to fix it is to replace the rear plate
Old 10-01-09, 11:54 AM
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is that on your old motor or the new block you picked up?
Old 10-01-09, 12:12 PM
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Are you sure they used a longer bolt or is this one of those times where someone didn't clean off the old sealant causing the issue?
Old 10-01-09, 12:43 PM
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repair

310141020870, ebay.co.uk. Have had good results on twinturbo manifolds with this. And i think it would be ok on yor repairs use it to glue in the boken bits and heat with a heat gun.As long as you get a good seal you prob dont need to repair anyway tbh.
Old 10-01-09, 06:06 PM
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it'd be nice if you could repair it, but those breaks are going to change the strength of the metal in that area and introduce new places for cracks to form.
Old 10-03-09, 10:49 AM
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Here is the reason why: the bolts for the engine mount were too long. On the right is the right length. On the left, the wrong length.

Last edited by GoodfellaFD3S; 10-03-09 at 11:19 AM.
Old 10-03-09, 11:01 AM
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Let a builder chime in, but I think I'd been looking for another rear iron. I could see the one in the last picture being an avenue for a serious oil leak. Surprised you didn't have one already.
Save the bolts. The longer one looks about right if you decide to install an old pan brace.
Old 10-03-09, 11:11 AM
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You need new parts. To glue, bondo, duct tape, jb weld, etc, etc will be jacklegged and you'll end up regretting it.

do it right, replace.



later
Old 10-03-09, 11:22 AM
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This was a mazda reman? It didn't come that way from the facility, the shop that installed your motor mounts used improper hardware.

I'd recommend calling them up and thanking them for the nice paperweight they indirectly gave to you.

Funny thing is we probably have about 70 of the oem bolts at the shop, because almost all engines we build get an oil pan brace so need the longer hardware.
Old 10-03-09, 11:55 AM
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Looks like someone might have tried to install an oil pan brace and used the wrong length bolts. This may have further been compounded by over-torquing them or using an impact gun. Either use a washer or get a shorter bolt, but I would still use the a brace.
Old 10-03-09, 12:33 PM
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Originally Posted by Sgtblue
The longer one looks about right if you decide to install an old pan brace.
Originally Posted by GoodfellaFD3S
This was a mazda reman? It didn't come that way from the facility, the shop that installed your motor mounts used improper hardware.

I'd recommend calling them up and thanking them for the nice paperweight they indirectly gave to you.

Funny thing is we probably have about 70 of the oem bolts at the shop, because almost all engines we build get an oil pan brace so need the longer hardware.
Originally Posted by Rotary Experiment Seven
Looks like someone might have tried to install an oil pan brace and used the wrong length bolts. This may have further been compounded by over-torquing them or using an impact gun. Either use a washer or get a shorter bolt, but I would still use the a brace.
You are all wrong. The shorter bolt (on the right) is the correct one that came on the Garfinckle oil brace. The shorter is THE CORRECT LENGTH. The longer bolt (THE WRONG LENGTH) on the left came on one of the other oil brace brands (I don't know which one for sure).

Lesson here is check the bolt length.
Old 10-03-09, 01:11 PM
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even with a brace the OEM bolts would be fine unless you have a 1/4" thick plate
i have seen this locally once when a guy brought me an engine
Old 10-03-09, 01:49 PM
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Well, we all might not be wrong if your thread wasn't so confusing

Did you just crack the iron now? was it like that when you pulled the engine? which bolts were used on the motor mounts? did you have an oil pan brace?

I think I just figured it out----this is the spare/core engine you bought? I just re-read the entire thread. How is what I said wrong? You have a junk rear iron, courtesy of somebody using a bolt that was too long.
Old 10-03-09, 04:53 PM
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Doesn't matter who's right or wrong.....what is right is his motor is screwed. Now tell us what you intend to do ?



Later
Old 06-13-13, 01:22 PM
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I cleaned the entire area with acetone, let dry, mix JB Weld with iron fillings blended in, applied it then waited a week before putting the motor together.

running 14 psi sometimes 17 psi for 3 years or 19,000 miles on top of the original 20,000 miles with no oil leak (except thru the turbo).

So there ... JB Weld works. The bad thing is that I had a motor built by Howard Coleman that has been sitting around for 2 years just because I didn't trust the JB weld. Oh well ...

Originally Posted by badddrx7
Doesn't matter who's right or wrong.....what is right is his motor is screwed. Now tell us what you intend to do ?



Later
Old 06-13-13, 04:32 PM
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