OK, all, some decisions have been made on the ongoing UIM repair process.

First of all, the board owes a big cheer to Boosty, who snagged four dead UIMs in a junkyard crawl last week, and sent them to me the lightning-like speed of the U.*. Postal Service. This should solve the inventory problem I've had, and cut the turnaround time for those of you who have had UIM failure and need one right NOW. Big cheer for Boosty!

So, here'* the deal. I've decided that the best solution to this problem involves the coolant block-off to the throttle body i described in a previous post. Although I plugged my own lower intake and will install it over Memorial Day weekend, I also posted in that thread my idea of just plugging the coolant passages in the UIM. I will of course still sleeve these manifolds, and it cures the problem some cores have of being too eroded to hold coolant well even when reamed out to the .875 ID for the sleeve. They will be sleeved, but also plugged, so that the coolant can't leak because it isn't present in the throttle body passages in the UIM.

Bill Buttermore and I have had discussions by PM about the possible throttle body icing, and have come to different conclusions. I plan to ignore it, after seeing some anecdotal posts on this board and others from people in cold climates who blocked throttle body heat and have had no icing problems, as well as consultation with a flight instructor buddy who doesn't see a problem.

For those of you who share Bill'* concern , I will continue to repair UIMs WITH throttle body heat, i.e. the UIM is just sleeved as they have been previously, without the coolant passages plugged. In other words, it'* your choice.

As soon as Boosty'* package gets here, I will start the degreasing process (really the worst part of it) and get these done. Due to some higher material costs, I am now charging $60 plus freight for them. When you've done the swap, I will happily pay freight back to me for your core.

Each manifold comes with Bill Buttermore'* .750/625 stovepipe. This means that, with the .805 ID of the sleeve, you have about an .090 air gap to dissipate heat. this is quite a bit larger than my original sleeved manifolds, none of which have yet failed (fingers crossed!) You're responsbile for gaskets, and please do the lowers while you're in there.

I've said this before, and I'll say it again: This is a time bomb under your hood. They WILL fail. Try to think of it as a preventitive maintenance item to keep from hydrolocking your engine.

May I hear your ideas and thoughts?

Best,

Bob.

awesome, Further Reasearch is awesome and will help all the L36 owners

I have to say great work, and keep the ideas flowing

Options are almost always good, especially if people understand the plusses and minusses of each option. Perhaps you could prepare something, maybe a FAQ or similar, explaining each option that you can give to people when it comes decision time? That way, they can make an informed decision.

Good work Bob, and three cheers for "The Dealer".

Props, Bob.

I can't stress enough how important it is to replace the lower intake gaskets. The factory gaskets on the L36s are absolute junk.

I'd like to add that Morty and TheFakeCanadian (aka Bonne94SSEi) assisted in the intake pulling effort. Need an intake off in under 5 minutes..we are the guys to do it. (it'* an ugly mess we leave behind though)

Glad to help out. Tons of parts came from that junkyard run and most have been donated to good causes happening here on the club. Bob and Bill Buttermore have done some amazing work and tons of research to help the members. We (Morty, Pete and I) were glad to lend a hand.

Not apples to apples, but us LT1 guys have been doing the "throttle body bypass" for years without a problem, even in cold climates. The LT1 routes coolant through the TB itself, but the idea is the same. I wish I would have plugged mine, as I sure as heck don't need to warm the intake air. I'm in Houston, where I rarely even have to turn on the heater for any reason.

I will be doing my UIM here in the next few weeks. I don't know if it is leaking or if the LIM gaskets let go, but I am losing significant amounts of coolant to the outside of the motor. Since the UIM is original and the motor has 192k miles on it, I figure replacing it is probably best. I have a new manifold in the garage with new gaskets and PCV valve. I read the Techinfo writeup on replacing these and it talks about a coolant elbow that needs to be replaced too. What does this thing look like? There is a translucent plastic tube in the intake that came with the set. Is this the elbow that is being referred to? Finally, does anyone sell JUST a sleeve for the EGR passage and, since I have the older model, I assume I need the reduced diameter EGR tube as well, or am I mistaken?

TheEngineer -- Please start a new thread to discuss your specific questions or else this thread will go off topic. Do a search for "coolant elbow" and you'll find more than you care to know about that coolant by-pass elbow.

I did a search and found the price, part number and numerous comments of "this should be replaced while you're there", but no picture or description of the actual part. I thought this topic was about the UIM repair which is why I posted here. Sorry for the mistake. I will start a new thread.