Dusterbd13-michael (Forum Supporter) said:Have you checked valve lash adjustment? I had one have a rocker loosen up and drop a cylinder.
No I havent. Though usually with a rocker that loose youd have some sort of noise associated?
Dusterbd13-michael (Forum Supporter) said:Have you checked valve lash adjustment? I had one have a rocker loosen up and drop a cylinder.
No I havent. Though usually with a rocker that loose youd have some sort of noise associated?
In reply to bonylad :
I didn't hear anything, but im half deaf from my time roadieing concerts.
I think I'd put a good old vacuum gauge on it and just check overall health vs point specific checks. Gauge can also tell you a possible cause for the low compression. Basically, I think you need to work backwards from where you are right now.
I don't see a head gasket failure, I mean it's the same crappy, been made forever sbc with two cylinders missing. If anything I have a feeling it's burnt one of the valves in that cylinder.
Ranger50 said:I think I'd put a good old vacuum gauge on it and just check overall health vs point specific checks. Gauge can also tell you a possible cause for the low compression. Basically, I think you need to work backwards from where you are right now.
I don't see a head gasket failure, I mean it's the same crappy, been made forever sbc with two cylinders missing. If anything I have a feeling it's burnt one of the valves in that cylinder.
Sounds fair. Either way the head has to come off. Ugh.
it didn't have P0306 before the intake was disassembled, is that correct?
In reply to AngryCorvair (Forum Supporter) :
Im not sure. Didnt run very well before hand. I dont recall how it ran to be honest. We have checked all the things I did mess with or replace and found no faults. May have been and I didnt notice because it ran rough. Im inclined to unofficialy say yes it did? IDK?
In reply to einy (Forum Supporter) :
At this point Id rather have that!
Well. Here we are. Obvious issues. Rear coolant ports blocked. Ran fine. Didn't overheat. But wow!
This was before I pulled the gaskets so you can see the state of them.
Interesting thing. These are cylinders 2 and 4. These ports look like all the others.
This is 6. Pretty clean comparatively. Thoughts?
bonylad said:Well. Here we are. Obvious issues. Rear coolant ports blocked. Ran fine. Didn't overheat. But wow!
Not unusual. Just goop accumulation. Flip your intake over and you'll see what I'm getting at. Those are blank ports.
In reply to Cousin_Eddie (Forum Supporter) :
Actually no. The rear two are coolant ports. Zoom in and you can see one is partially clogged and the other fully. After those pics I scraped them out with a vacuum and chunks of corrosion and build up got sucked up along with some coolant lol. Spoke to several people and considering how the rear coolant port was obviously leaking and how clean 6 is compared to the rest.....theory is 6 was missing due to coolant leaking into intake port causing the miss and cylinder wash down (hence lower compression which at this point I'm not even sure I did the compression test right).
Makes sense!
In reply to bonylad :
he meant they're blank on the intake side so the blockage doesn't matter. the blown intake gasket theory still holds up though
In reply to turbojunker :
Oh! I stand corrected! Good to know it's actually normal and I don't have some larger issue. Thanks fellas!
The only reason those rear coolant ports are in the head is so GM could cast one head and use it on either side. So they just blanked off the intake manifold and the ports are "dead end". To not have this scenario, GM would have had to have specific left and right side heads with no rear coolant ports and the added cost and inventory issues associated with that.
It's been working on small blocks since the 1950s so the concept is sound.
Blessed part of this is I get to clean!
Before.
Degreaser and power washer time!
Spider assembly checked good. Cleaned it all up. Never remembered how handy a tuck bed was. Mobile tool bench!
Now is the time to check those EGR passages and make sure they're wide open. It might stave off a future fault code.
In reply to Cousin_Eddie (Forum Supporter) :
Yes sir. Did that with degreased and the pressure washer. Good flow!
Made some progress. Gaskets came in.
Surfaces all ready to have the intake installed.
Slapped the cleaned valve covers on.
Fit the lower intake gaskets. Quite robust. Should be an improvement.
All for now. I intend to get it back together tommorow or Saturday. I was gonna for the intake then realized I never cleaned the bolts. They were dirty.
So I fitted my replacement mirrors. Stock and looking better. Apparently it had one power and one manual mirror. Smh.
Bonylad love the effort you are putting into your grandfather's truck. It is really good to see such work being put into a run of the mill, everyday old pick up truck. Enjoy it once you have it up and running again!
In reply to bigbrainonbrad :
Thank you for the kind words!
Well it's all back together and runs more or less the same. Idk. Losing my patience with the 4.3. Looking more and more at a v8 swap. Mounts are cheap. Use my trans. Have a 305 that could be breathed on.
Smh.
Off topic met a guy today and picked these up. Third gen Trans Am GTA WS6 wheels. Staggered set up. Tires are junk. Good thing about this setup is I may not have to run spacers. Third gens had less offset on the factory wheels compared to a vette or camaro.
On a first gen. So very similar to this.
I will drive the truck a while to see if the miss clears up. May be washed out cylinder. Idk.
I will also post up the wheel resto. Not going for brand new as I wanna keep the patina going.
Update. Praying and hoping I figured it out. Whether or not the intake leak was the issue it was an issue. I checked my distributor and found excess play up and down and left to right. Abnormal wear on the gear and it's a aftermarket part that's been replaced. Very very interesting. Plus abnormal wear on the cap as well.
Those GTA wheels are going to be incredible! Great pickup.
So. Here are pics of the dizzy.
Abnormal wear on the gear and abnormal wear on the cap. Ordered a new dizzy. Also note the rust in the top of the shaft.
The wheels are not staggered. They are all the same size. 245/50. So that's even better, a square setup!
So while I'm waiting on the dizzy. Pulled the dash to pull the radio to install the Bluetooth.
Put the tailgate back on. Something hits with the roll pan and I ain't messing with it. So it's latched with one bottom latch and two top latches. Plus cables. I don't plan on dropping the tailgate anyhow so. I yanked on it. Solid. May at some point redo the roll pan or make it purty but for now. Patina hot rod roadkill......except functional parts. That has to be perfect.
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