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Old 12-11-2007, 07:19 PM
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LT Texan
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Default OB Motor Mount Questions

I'm pulling the engine soon to freshen it up a bit, replace those cracked and leaking 30 year old gaskets, install euro S heads and cams....

Of the things to do while I'm in there, I'd like to know if anyone has experience with the OB motor mounts. These are the early solid ones. Do these "wear out?" The new ones are a bit pricey. (That and everything else!) But it will be dumb not to replace these with the engine out - if necessary.

Also, the left hand side engine shock (an old bugger thing?) is AWOL. Always has been since I had the car. The one that was there obviously is not damping as it did when new. Shocks are a bit on the pricey side, too. And I am wondering if these are really needed. I could always do the old hot rodder trick of using a bit of cable as a safety strap to restrict how far the engine can twist.
Old 12-11-2007, 07:40 PM
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Sean79 5spd
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No question, replace the engine mounts and shocks. Do the rack mounts, fuel hoses , power steering hoses, clutch blue hose as well.

Sean
Old 12-11-2007, 08:07 PM
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Blue hose of death. It's on the agenda.
Old 12-11-2007, 08:21 PM
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nosnow
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Since the engine is out I suggest replacing the slave cylinder and the coolant expansion tank. Probably over kill but if you've ever experience a clutch master replacement it is a huge headache if the engine is in.
Old 12-11-2007, 09:24 PM
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Dan,
I have the silicone oil pan gasket for $40 and the MM's for $137.95 each.
Let me know if I can help you on any other parts?
Roger@928sRus.com
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Old 12-11-2007, 09:29 PM
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djurek
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I love your car. Be gentle with her.
Old 12-11-2007, 09:40 PM
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Mrmerlin
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I think Sean was referring to the clutch master cylinder, if the engine is out you should actually replace both the master and slave and the blue hose also remove the master cylinder resivour wash it with some brake cleaner followed with simple green and hot water finally rinse it out with some isopropil alcohol with a blow dry with a hair dryer.
Are installing any other intake parts besides the Euro cams? you might be better off if you can as the intake parts for a Euro are bigger and will give more HP with the cam setup
Old 12-11-2007, 09:57 PM
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dr bob
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Dan-

You have the option to replace the crossmember with a later one, and install the later mounts. The savings on the mounts and that shock should easily cover the cost of a used late crossmember. Easy to change while the motor is out.

Contact one of the breakers for the crossmember. I'll let others let you know which motor mount to use. I personally favor the real hydraulic mounts, while others insist that the solid American replacements are adequate. Your decision, but an easy one all things considered.
Old 12-11-2007, 11:13 PM
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Originally Posted by dr bob
Dan-

You have the option to replace the crossmember with a later one, and install the later mounts. The savings on the mounts and that shock should easily cover the cost of a used late crossmember. Easy to change while the motor is out...
Is nothing simple? Later crossmember so I can use later mounts and have the option of solid mounts.

Originally Posted by ROG100
I have the silicone oil pan gasket for $40 and the MM's for $137.95 each. Let me know if I can help you on any other parts?
yes yes ($40), no no (137.95)
Old 12-11-2007, 11:20 PM
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Originally Posted by Mrmerlin
...Are installing any other intake parts besides the Euro cams? you might be better off if you can as the intake parts for a Euro are bigger and will give more HP with the cam setup
Yeah, I have the whole top end. I bought it from some guy in the UK while I was living in London. I have the bigger throttle body, manifold and runners as well as the LH jet? parts (injectors etc). But I don't think I could get the non-mechanical stuff sorted out.

When all is out and the block and the heads are at the shop, I'm going to try a bit of mix and match. I don't think the CIS throttle body is restrictive. But to fit it to the Euro S manifold and runners would be nice. We'll see.
Old 12-11-2007, 11:21 PM
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Originally Posted by djurek
I love your car. Be gentle with her.
thanks. After 18 years if ownership, I'm surprised she hasn't left me.
Old 12-12-2007, 12:59 AM
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Originally Posted by Dan Perez
Is nothing simple? Later crossmember so I can use later mounts and have the option of solid mounts.


yes yes ($40), no no (137.95)

That's about right. The later style mounts don't require the external damper, so there's a real cost advantage if you can get the later crossmember easily.

There are aftermarket hydraulic mounts from reputable makers, something more reliable than the ones that spill their fluids out in the first few months of use. Otherwise, the "solid" mounts from Carl or Roger are durable but don't offer the same isolation as the hydraulics. This discussion is just a little south of the "which motor oil?" question.
Old 12-12-2007, 04:02 AM
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Good luck, take lots of pics and post up progress!
Old 12-12-2007, 05:17 AM
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marton
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Basically the solid mounts do not wear out; worth a visual inspection to check if they look OK (not torn or ragged)
I would not change to hydraulic mounts on my 82; they simply do not last as long and I doubt there is any difference in the "feel".

Marton
Old 12-12-2007, 07:52 AM
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Solid early mount and small shocks are package deal. I would make sure both are ok.


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