I'm starting to go over more closely the junkyard 4.3 Vortec I pulled to put into the Blazer and am trying to determine exactly what level of getting into it I want to do before tossing it into the truck and seeing what happens. I want to do (and spend) as little as possible for it to be reliable and drivable (as has been covered a bit in a previous thread)
Looking it over, I noticed that there is a good bit of gunk on the back of the passenger-side head whereas the driver's side is a lot more clean. It's a mix of light and dark-colored grease-like material. My concern is that it's oil and coolant that have leaked out from under the head- but also realize (since the knocking engine I pulled was also significantly dirtier in the same spot) that it could just be normal for gunk to collect there. What think ye? Below are the pictures of the two sides...
Passenger side (one I'm worried about): 
Drivers side (for reference): 
Thanks!
Looks like normal gunk to me; the lighter stuff could be some sort of sealant. Why not do a leakdown test before installing it to be sure?
I'd do a thorough degrease of the motor then inspect that head to block spot of the suspect area.
You was gonna paint it anyway, right?
Clean it up and slam it home. If the oil looked good, quit worrying.
Still haven't decided on whether I'm going to paint it or not- I'd like to (like engine bays to look nice, and figure it may help in selling it if it looks clean) but may be lazy and just clean it up. Doing a leakdown test isn't a bad idea- had planned on a compression test, but don't currently have a leakdown tester. Will have to see if that's one of the loaner tools I can get, or just drop the $40 on one from HF.
I haven't drained the oil and dropped the pan yet- that's what I'll likely be doing next (and possibly replacing the rear main seal) along with pulling the block coolant drain plugs.
Got started cleaning up the engine, including draining the oil... and it's not looking good...
It's looking like this engine isn't going to be just a simple clean and toss into the Blazer. Technically I could take it back and get another from the junkyard- but that would be a lot of time, and honestly I'd halfway wanted to do a more thorough rebuild- so I figure I should be able to get one solid engine between the old and 'new' one...
Change the intake gaskets. Use the expensive aluminum Felpro gaskets. Ignore this step at your peril.
That doesn't look like headgasket milkshake to me.
It looks a lot more like condensation from sitting outdoors or lots of short trips.
I'd put it in and run it a while to see what's going on but lots of folks like making work for themselves.
Shawn
A head gasket is so easy with the motor out I would just go it. At this point taking I down to a short block and back is an afternoons work. I would consider a oil pump and a water pump as well.
Yeah, I'm figuring a head gasket is a smart move. I'm also probably going to take one set of head to be hot tanked and inspected to make sure they're not cracked, I just need to decide which set to take...
At this point id do head gasket, valve stem seals, and check a few bearings. I might even do a ring and bearing rebuild if the cylenders and crank look good.
But you hit water. Time to go deeper.
Streetwiseguy wrote:
Change the intake gaskets. Use the expensive aluminum Felpro gaskets. Ignore this step at your peril.
All this.
The pictures look normal for a leaky intake gasket. They drool down the block deck and they drool into the oil.
I would change the intake gasket before the engine's in even if the current one is OK...
What others have said. While the engine is out go through everything. Dunno what the budget is but at the end of the day you'll have peace of mind you didn't miss anything while you had the perfect opportunity.
The budget is 'as little as I can spend' with a timeline of 'SWMBO is annoyed at having so many non-functioning vehicles'.
It sounds like at a minimum I need to replace the intake gaskets (had already picked up a new set of them), and should probably just go ahead and do the head gaskets (and new head bolts) as well- don't have those picked up yet, but Amazon can have them here almost by when I'd really need them anyway. I'll call and find out a price and timeline from the cylinder head shop on Monday and decide about that once I have that info- if it will cost a lot more than I'm thinking or take a really long time for him to get to it I may just have to take my chances with them being ok.
My guess from the pictures is a leaky intake gasket. That rear port would be a water jacket on a V8 so assume it is on the 4.3 as well.
Got into actually taking things apart on the engine (I'm glad I have two because the EGR line on the 'new' engine WILL NOT unscrew from the manifold...) and am again having to reconsider what exactly I think is appropriate to do before putting the engine into the truck- but in a good way this time.
VERY clearly the intake gasket failed in multiple places, and easily explains the coolant in the oil as well as the gunk behind the cylinder head. Ironically the intake gasket on the original engine looks to be both an improved design and in near-perfect shape.
So now I'm back to deciding whether it's really necessary to pull the heads (and the exhaust manifolds to do so...) or if I should just properly install the new intake gasket and leave the heads alone.
I would take a chance and leave the heads alone, intake gasket looks like the culprit. Because if you have my luck, at least one exhaust bolt will break off and end up costing you more at the machine shop to remove them.
81cpcamaro wrote:
I would take a chance and leave the heads alone, intake gasket looks like the culprit. Because if you have my luck, at least one exhaust bolt will break off and end up costing you more at the machine shop to remove them.
That's definitely what I'm leaning towards doing- I didn't have any problems with the exhaust manifold bolts on the old engine (as I couldn't get the exhaust flange nuts off before pulling the engine and instead unbolted the manifolds), but would definitely prefer to not have to do the extra work of pulling and re-installing the heads if it's not absolutely necessary.
That's what they normally look like. Nothing to see here, move along. Intake gaskets turn themselves inside out all the time.
