Intake? Sometimes. If I recall correctly you need some silicone in a few places. More annoying than difficult.
No, exhaust, heard itās whistling on the left side from the front.
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I think the only difficult part of an exhaust manifold gasket would be the rusty nuts and bolts.
If you have any old automatic transmission fluid and some acetone, mix then 50/50 in a glass jar and shake vigorously, then apply it to the nuts to help lubricate the studs.
I say a glass jar because acetone can melt certain plastics from contact.
You may need to separate the manifold from the intermediate pipe so it can move around easier.
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And always, always wire brush as much as possible the heat rust off of the exposed threads Before applying lube or penetrate. And then trying to remove. The grown rust particles will bind up movements.
Rattling the bolts heads flats or nut flats with an air chisel with a flat nosed bit does wonders too to loosen up the heat seized and shake off the binding rust particles too.
S.U.
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I agree with others - the rusty nuts and bolts are probably the worst part.
When I was up for inspection in February I replaced the cat on the Volvo and the manifold gasket couldnāt take the abuse wiggling the exhaust. Only days later a leak developed on one cylinder and the car sounded like a one cyl hot bulb engine 
Dismanteling the manifold I broke a couple of those threaded rods. I had to drill holes in them and use a āgrispittā (which I donāt dare to translate ) to get them out.
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Thanks for the tips, Iām going to order some stuff from rockauto, so I can get it home before the inspection.
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Grispitt might be called an eazyout here. They work great for filling up the hole you drilled in the broken stud. You insert them and in a couple good twists they break off and there is no way to drill them back out. I may be a little bitter.
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āIFā you break off any form of extractor you have 2 options. Fix it with fire and melt it out, or a quality cold chisel and break it out piece by piece.
That being said we are half way to all the needed information here.
- Wire brush clean as can be
- HEAT to a dull cherry red
- Spray to cool with some form of penetration oil (atf/acetone is a good option, pb blaster, WD-40 ext)
- Air hammer smacks on the flats, a flat drift can do the job as well
- Reheat and penetrant again
- Impact driver out
This is my standard method of operations for a questionable exhaust bolt or stud. Each step performs something different to the hardware, Steve had some great details on that.
We use the heat to expand and the penetrant to contract the bolt, breaking loose internal bolt shank-on-manifold rust. Air hammer furthers this action. Rattling loose rust particles for ease of movement. When this happens allows the penetrant to seep further back reaching threads. The repeat procedure just furthers all these actions. The impact driver is a 50/50 it either comes out or it breaks, then extraction begins which is a different problem to solve
I have not had many problems with 4.3 Chevy manifolds over the years I donāt recall to many broken bolts. If I had, I would have a baggy of them in stock in the bottom right drawer of my tool box like I have ford head pipe studs, ford triton manifold studs and nuts, dodge manifold bolts, and Chevy LS manifold bolts. I have no other Chevy hardware so even if memory did not serve me well, what I kept in stock tells the story of the problem exhaust trucks
That being said letās see some pictures of the manifolds and their hardware. Your local climate may change how the hardware has aged on the truck and we can come to a better conclusion then discussing what may happen in a worst case scenario
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Maybe thatās why they are called grispitt - not very impressive
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As in most things there is a lot of opinions.
Only Done-It experienced opinions should be valued.
I do like the Project Farm guy and use many of his comparisons for choices.
But this time his method testing is a big-fail on the extractor sets.
The object of a broken bolt extractor is to remove the problem stub and get going forward with the job being held up.
NOT prove who makes the best before breakage numbers!!
What I found once you are stuck in a hole with a break off to do was to small drill all of the way through the stub.
This lets you get in behind it with penetrant spray too.
Then I found after much trail and error to only use the four cornered long narrow tapered extractors. Those are corners longwise milled with a groove making for eight biting edges.
All of those pound-in short tapered many edged spiral fluted tips cannot but cork-in-a-bottle push outwards locking the broken off stub even tighter into the threaded hole. Stupid.
Yeah. They do not break off. They strip themselves and the hole you drilled most often.
Back to my long taper square flat types. Select the best for the stub diameter.
Then re-drill halfway down with a LEFT HAND drill bit. Yes create a stepped hole to kind match the extrator bits taper. Ha! Many times at that point the twisting of the lefthand drill bit will spin the broken off stub out. (Iād tell apprentices it got scared out avoiding the follow on brutalization.)
Then only lightly to moderatly tap in the extrator bit. Now with your clamped down tap handle carefully with even pressure turn it out. Wiggle some both ways. Buy/get a second Tap handle and clip its handles short for restricted areas working.
I do have the different square 3/8 drive sockets. Nearly impossible to not apply side pressure with standard ratchet or an adjustable wench. Thatās how skinny extractors get broken.
And I have gotten extractors stuck. That stub just not going to come out. With a clamped on tap handle you can two side pry upwards and remove it. If you do not break it off. Then you are onto over-drilling it out and tread-inserting. Big specialized job then.
Project Farm had a great video test comparison up on those.
The long taper square fluted extractors are relatively cheap. Cheap to replace when worn or broken.
The GOOD drill bit sets are expensive.
And a good speed controllable air or electric close quarters right angle drill even more expensive.
All-in-all do everything possible not to bolt/stud break in the first place.
Rounded bolt heads or nuts? Much easier. Drill off the head. Pressure relived they will most often then lefthand drill spin right out.
Nuts; Dremel tool two sides slit the nut then chisel open and off. You get points for not damaging the bolt or studs threads.
S.U.
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How do the flat rate books deal with pulling old exhaust manifolds? I wasnāt aware of the left hand bits. I can see the advantages.
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Every shop I ever worked at a broken bolt was a extra hour book time. Depending on skill of the tech and front counter guys morals it was not always charged. This was also dependent on if customer had already fingers in fudge things, or if parts were broken on arrival. I have had a set of ford triton v10 manifolds that ended up at 21 hours billed due to broken bolts.
From experience there are jobs I will turn away now. Some heads off send to machine shop. Faster. Time and money efficient.
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Marcus is correct - at most 1 hour for broken bolts. Bear in mind the Tech has to personally also buy the special tools, gain the experiences - so it never, ever pays enough. So the value was to get known as the aways gets the overall jobs done guy; so assigned higher probity on work given. NOT be the guy let go on slow down periods.
I earned more in labor trade value doing it for other Techs. Always a way for pay back in something I could not do. Or could not do solo.
And here in virtually no-rusts mid-state I never ever once could get extra pay for Canadian, midwest visitor vehicles or ones from the salty ocean coast to slow and take the times to NOT break badly rusted bolts and nuts. Fish out and use the replacement bolts and nuts from my own personal scrounge stocks.
The Shops did pay for the torch hot-wrench fuels though. So as Marcus said heat the fear-into-them as can be done safely.
And I was never once reimbursed for using my easy clean up Halon fire extinguisher either.
Never made a claim for something that ānever happenedā, eh. Now their white powder extinguishers, if used: was impossible to not-see, and just have it be a never happened. Reports. Reports. Reports.
S.U.
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Most or many of my broken bolts came out welding a nut on the stub- and the welding heat also helps loosen the bolt- other wise it was as usual, have some good hard drills on hand and an easy out. NOW i got to go look see what you guys may have done getting out broke bolts.
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I have welded a nut on a broken stud as well Kevin but never managed to do it on an exhaust manifold still on the engine. I suppose it would be more doable with MIG but not really with stick.
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I saw youtube once where they inserted a short piece of piping that fit into the hole. They put a welding rod into the piping and let it burn the broken stud and the bottom of the pipe for a little while. I think you will have to have quite a bit of luck to get a good enough weld in there to take any tourqe though. Also, you may risk weld the stud to the engine.
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The wife drives a volvo v50, and when I back it up a hill the whole car shakes, is it a bushing or could it be the clutch, they think it feels like a bushing, but canāt find anything bad.
Applying heat to a rusty nut and bolt often helps a lot. A rusty old nut at the exhaust often just become rounded if you apply some torque with a wrench. So remove as much rust as possible, maybe try some penetrating oil. But the best is, heat it up with a torch to a dark orange. Best is a acytelene and oxygen torch, as the flame is very concentrated. A normal propane torch has a bigger flame, so you heat more of the surrounding. Then it is often possible to unscrew it with very little torque on the wrench. The heat expansion breaks is loose.
Only problem with newer cars is, that there should be no plastic or electronics too close to be damaged by the heat. And of course no petrol linesā¦
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Are the motor and transmission mounts in good condition?
I am not very familiar with manual gearboxes shuddering, I donāt have a lot of experience with them. Just giving a tangential suggestion that could also give shuddering.
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Itās the motor mounts that I think are the fault, but have changed it as I thought, but there was no difference, must try to have someone look under the hood when I reverse
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