So I'm told by the mechanic that I've got an intake gasket problem, he took me under the car and showed me where it is leaking. Of course, they want to fix it, and replace the water pump, serpentine belt, etc while they're at it. Looking at $1500 to fix.

Couple questions-how urgent is this fix? Am I going to damage my engine if I let it go for 5-10K miles? Do all those other things need to be replaced at the same time, or is that just them trying to upsell me?

Also, is this something that I could do myself? I don't really do engine work, but I've done a lot of suspension work recently and would consider myself somewhat mechanical-messing with the engine just scares me, most I've done on it is change out the T-Stat.

While I'm at it, I've been considering some engine bay mods for a while (although, as mentioned, I don't know much about it). I keep my engine pretty clean, but wondered if there's anything that I should replace/have the mechanic replace as part of this, to make it look nicer/run better? Figure if the engine will be apart anyway, might as well take care of any engine mods at the same time.

I should mention I have the 3400 engine, not the 3800-which leads to my final question. If I am going to all this trouble, I've seen decent looking 3800 engines for $1000ish on Craigslist-would it be better just to go for the bigger engine + install? That sounds a bit far-fetched, but keeping my options open, I guess.

Appreciate your help/opinions!

 

I've done intake gaskets on 3400 and 3800 engines. The 3800 is easier IMO.

The water pump and belt on the 3400 is super easy (and I think the pump is like $30).

Now doing the lim, you're not much further from doing the head gaskets. Might be worth considering.

If you do just the lim gaskets, get the Fel pro metal core gaskets. You're probably looking at $100-$150 in parts for the lim gaskets and fluids.

I believe there are some YouTube videos on how to do the job (3100 and 3400 are the same exact process).

As for risk, typically coolant bleeds into your oil. Longer this happens the more you are risk of damage to bearings and such. I'd advise not waiting too long and get it done soon.

 

Thanks for the input Maniac. I'm religious about oil changes, so I'm hoping any coolant that's leaked into the oil has been minimized that way.

I'll look at some youtube videos and see if I feel comfortable doing it myself-if so, that could save me a bundle, because they're wanting to charge for 10 hours labor at the shop.

Might just do the head gaskets too, if they're not much more work. Any recommendations there?

 

i plan on doing mines this spring, im doing all the research i can, i had my shop do it for 500 with my last engine

 

That is a much better price than I was quoted-will watch some youtube tutorials when I get home from work tonight I think.

 

I did a quick skim on the video below (it's long, but the guy really seems to go step by step).
If you are going to do this your self:
- great time for new plugs/wires. Also, when removing the pushrods, they are different sizes (unlike the 3800, the pushrods need removed when doing the LIM gaskets).
- When I've done this, I took sandwich bags and one rod and rocker in each bag, labeled them in a way that I would remember the order. If you mix the two different sizes of pushrods, you will damage something upon first start. It's easy to keep them organized.
- Take your time and CLEAN everything. Last time I did a set of head gaskets, the heads were so clean you could eat off them. You normally don't go this far down on a car, it's worth some time de-gunking stuff and pressure washing.
- You do NOT have to send the heads out. Even the GM shop book will tell you to just check the decking surface with a straight edge (looking for signs of where the straight edge does not travel cleanly/evenly across the surface of the head).
- Don't get worked up about this guy's Dex cool statement. The issue he found happens if you don't do regular coolant flushes (which should be done regardless of which coolant you use).
- Save yourself some grief, do NOT disconnect the fuel lines from the fuel rail. The one has an O-ring in it that has personally caused me a headache on one of the cars I worked on. You have plenty of room to pop the rail and put it to the side, out of your work space. Do make sure you get new injector O-rings for re-assembly.
- A lot of people recommend new head bolts (because they are torque to yield). I've re-used head bolts and never a problem. It's not like you take head bolts in and out all the time. This will more then likely be the only time those bolts will ever be re-used.

The job does take some time and does look intimidating, but it's actually pretty easy if you are willing to take your time. I hope those tips I gave above help if you do go forward.

As for cost of the LIM on a 3400 vs 3800, I've done both. Honestly, I feel the 3800 is a cake walk. Just seems like there is less stuff to do/remove.

 

Thanks for all the help! I am definitely a bit intimidated, but might still go ahead and try it.