Manifold Advice (1 Viewer)

[ace7141]

Ok wise ones - I got my manifold off, replacing gaskets and finishing the desmog.

What can of worms would I be opening if I split these two manifolds? I understand that if I do so, I would probably need to get resurfaced.

Also any advice on best course of action to safely clean the outside of manifold? What cleaners/chems do you recommend? There is rusty, with some pitting in areas. I would like to do whatever is most effective to protect and preserve the manifold. I have never refinished anything of this nature before.

I have purchased a stud kit from SOR to replace bolts when putting manifold back on block. Are these stainless steel? Couldn’t tell from description on SOR website.

I’m sure I’ll have more questions..

 

[NeverGiveUpYota]

For cleaning it depends on how much time you have and how deep your pockets are. I went cheap on my exh mani. I dipped in molasses 1 gal to 5 gal water for 14 days and all the rust scrubbed right off.
For the intake just buy some EZ off oven cleaner and it’ll clean up w/in minutes. Wash it off well after and dry.

 

[ace7141]

Sweet (literally)! You used molasses? I am intrigued. Thanks for the advice!!

I am always looking for the budget-friendly route to take, but want to do it correctly with no shortcuts. I am trying to make it to the Cottonland Cruiser Camp-Out at the end of April, so don't want to rush the process, but time is of the essence. Also I'm eager to drive my truck again.

Would using a gel/spray on rust remover product have any adverse effects? I have used it on all my other parts thus far with great results, but those were small bits compared to the manifold.

I do plan to wipe clean the surface that mates to block, and remove all the old rtv sealant. I have read its best to put on manifold gasket dry. I have a Remflex gasket set just waiting in the corner.

 

[OSS]

Cleaning of any rust on the exhaust manifold will only be a temporary cosmetic exercise. If you drive the car regularly, it won't rust significantly. The real rusty ex manifolds got that way because the car wasn't driven. I'd just wire brush it and be done with it.

Toyota never intended for the manifolds to be disassembled (although it's possible and everyone does it). Their recommended "fix" for a messed up/warped manifold was to replace it. But that can't be done any more.

If you split them apart, you'll need to have them machined (as a bolted together unit) flat on the flange mounting surfaces so it mates perfectly flat with the head.
The weak part of the 2F engine is the lame manifold situation. Vacuum leaks along the manifold are very common on these old engines. If you split it and try to bolt it back together without it getting machined flat, that's a wide open door invitation (with appetizers and party balloons) for a manifold leak.

 

[NeverGiveUpYota]

Yeah tractor supply sells it buy the gallon. I did it in the winter and had a big plastic planter I soaked it in. Kept it covered and checked it every few days. It was really easy.
I’m essentially a single stay at home mom, I work part time and don’t have a ton of cash coming in so I wanted to go cheap. It worked. I painted the exh w/ high temp paint and cured the first two cycles in my oven and the last on the truck. It looks okay, could be better but it’s what it is.
I had mine apart, I had them planed, they did a s***ty job, a friend who is an airplane machinist took the intake to work and flattened it a smidge more because we found it was cupped on the end ports. So taking it apart has its risks. I’ve had them off more times than I want to say. I believe I still have a slight leak but the truck runs. If I pull them again I’ll add two gaskets and call it done.

 

[NeverGiveUpYota]

Sweet (literally)! You used molasses? I am intrigued. Thanks for the advice!!

I am always looking for the budget-friendly route to take, but want to do it correctly with no shortcuts. I am trying to make it to the Cottonland Cruiser Camp-Out at the end of April, so don't want to rush the process, but time is of the essence. Also I'm eager to drive my truck again.

Would using a gel/spray on rust remover product have any adverse effects? I have used it on all my other parts thus far with great results, but those were small bits compared to the manifold.

I do plan to wipe clean the surface that mates to block, and remove all the old rtv sealant. I have read its best to put on manifold gasket dry. I have a Remflex gasket set just waiting in the corner.

Don’t use the remflex between the two w/ the heat riser. Plenty say they couldn’t compress them enough for the bolts to fit. You can get the gaskets at Napa, blanking on the brand name tho!

 

[ace7141]

Roger that on the wire brush, OSS! My thought as well. I don't really want to paint it. I am afraid it would just peel and flake off eventually anyway. My concern was more preventive, and protection from further wear and tear.

Thanks NGUY! I think for the time being, I am just going to clean it up, and use the remflex on the main mounting surface. I have anxiety about taking the two manifold pieces apart, and from what I can tell there is no leak there.. yet.

I will be anti-seizing all bolts when it is put back on, as I assume I'll eventually have to tear it down again at some point.

The good news is my intake was not cracked in the usual trouble spot, so I will take that "W".

 

[ace7141]

Ok. Manifold is back on! Truck is running. I have a question, and maybe I am being too cautious..

What temp should the intake manifold reach? I drove the truck around today, after topping coolant and oil off. Once I parked it, I was curious and got my laser temp gun to see what surface temps were around the exhaust and intake manifolds. My intake manifold is reaching temps near 250+ and it was concerning. But to be fair, I don't know what temp it was reaching before this.

I also only torqued the manifold to the lowest ft lbs recommended by the FSM - 29 ft lbs. I think I still have a small exhaust that could be fixed with re-torquing the bolts to 30 - 32 ft lbs perhaps. The FSM says 29 - 36 ft lbs, which I though was a wide range.. Would still having a slight exhaust leak raise surface temps on the intake manifold?

My temp gauge in the dash still reads normal operating temps, nothing has overheated that I can tell.

 

[WSOPgold2012]

I don't know anything about anything so, don't ask any tricky questions but, I just had mine machined along with machining the ceramic headers to match....it's was CHEAP!! like $40 . While there ya may wanna switch to headers. Have fun!


Ceramic headers I used: FJ40 FJ60 Headers Ceramic Coated Tuned F and 2F Engines Man-A-Fre 1968, 1969, 1970, 1971, 1972, 1973, 1974, 1975, 1976, 1977, 1978, 1979, 1980, 1981, 1982, 1983, 1984, 1985, 1986, 1987 SKU: 17100-40ST - Landcruiser Parts

Another header thurd: Man-A-Fre Header / Heat on Power Steering Pump

 

[BlackCat]

Ok. Manifold is back on! Truck is running. I have a question, and maybe I am being too cautious..

What temp should the intake manifold reach? I drove the truck around today, after topping coolant and oil off. Once I parked it, I was curious and got my laser temp gun to see what surface temps were around the exhaust and intake manifolds. My intake manifold is reaching temps near 250+ and it was concerning. But to be fair, I don't know what temp it was reaching before this.

I also only torqued the manifold to the lowest ft lbs recommended by the FSM - 29 ft lbs. I think I still have a small exhaust that could be fixed with re-torquing the bolts to 30 - 32 ft lbs perhaps. The FSM says 29 - 36 ft lbs, which I though was a wide range.. Would still having a slight exhaust leak raise surface temps on the intake manifold?

My temp gauge in the dash still reads normal operating temps, nothing has overheated that I can tell.

Whatever minor exhaust leak that is present now will only grow by driving it more. The longer it leaks the more gasket it’ll blow out. Get it sorted ASAP.

 

[ace7141]

Absolutely. I will be re-torquing everything in the next day or so, don't plan on driving. I am using Remflex gasket, and think there is some room to still close whatever gap may be present. It is immensely better than it was. The exhaust leak was terrible. Now it sounds like a slight whistle, like exhaust leak is just barely creeping past gasket.

 

[WSOPgold2012]

Absolutely. I will be re-torquing everything in the next day or so, don't plan on driving. I am using Remflex gasket, and think there is some room to still close whatever gap may be present. It is immensely better than it was. The exhaust leak was terrible. Now it sounds like a slight whistle, like exhaust leak is just barely creeping past gasket.

I never noticed my exhaust leak... my manifold was warped and never knew until putting on headers!!! after discussing it here came to the conclusion the safest way to machine the parts...i have no interest in tearing it down again any time soon!!!

 

[ace7141]

I was going to have them machined, but when I put a straight edge to it, it didn't look off by much at all. So I went with the Remflex gasket. i feel that a little more torquing of the bolts will fix this issue.

Anyone have any isight to the manifold surface temps? I realize its close to the exhaust manifold, and surrounding temps could lead to high surface temps on the intake..

Again.. maybe I am being overly cautious.. but wanted ask the hive mind what they thought.