Rough idle, compression test... head gasket at 3 and 4? (1 Viewer)

DFXR

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Yup. Makes the 2nd time (unfortunately, there sometimes is one) much much easier.

Any idea what HG was used on the rebuild? ...

I don't have my new Toyota head gasket in hand yet to compare, so I am not sure what the old one is. If you look at the pics in post 18 there is a red line along the edge on the pushrod side of the gasket, maybe that is a clue for someone who knows more than me?
 

Spike Strip

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Not a Toyota HG. Looks like FelPro or Stone. Be sure an use the 61030 HG, it's the updated one for supposedly better coolant flow.

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Spike Strip

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Sheet, I already ordered the 61010 version from City Racer
Well, if your truck is a 85 it has the 2F/3F head so a better choice is the 61030 HG. The 61010 is spec'd up to 10/84, after that, because of changes to the casting of the heads, Toyota went to a 61020, which was then superseded to 61030.

I'd see if the part has shipped yet. I'd only want to do this once, and do it right. Toyota changed part #s for a reason.
 

DFXR

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Well, if your truck is a 85 it has the 2F/3F head so a better choice is the 61030 HG. The 61010 is spec'd up to 10/84, after that, because of changes to the casting of the heads, Toyota went to a 61020, which was then superseded to 61030.

I'd see if the part has shipped yet. I'd only want to do this once, and do it right. Toyota changed part #s for a reason.

It's a 10/84 manufactured 1985. The head has a 61040 casting number on it.
 

DFXR

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What do you all use to clean up the block deck and tops of the pistons? I am thinking I would scrape the block surface (carefully) and hit it with a red scotchbrite, but what solvent, and what abrasive do I use on the pistons?
 

lcolon

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I would try not to use scotchbrite. That stuff deteriorates and leaves residue and scratches. For the deck, just a plain old paintscraper. I have 2 that I use that you can get at any hardware store: Wall Paper Stripper and putty knife

Whatever you do - do not use a die grinder with a sanding attachment! That will change the level of the block.

That should get the top of your block nice and clean. Stuff the cylinders with some shop rags to keep the residue out. Be careful around the coolant passages and pushrod tube locations to not get any crud down in there. If you get some stuff down the pushrod holes, pull the sidecover off and clean it out. Anything in the coolant passages would require a flush.

I would check the top deck with a machinists straightedge. If you don't have one, I can give you a recommendation or since you are local, PM me and you are welcome to borrow mine.

Spray the top with WD40 when you are done cleaning it or if it is going to sit to avoid surface rust.
 

DFXR

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Head bolt question-

I read in the following thread that the original, re-usable 2F head bolts were replaced somewhere along the way with updated bolts (torque-to-yield or semi-stretch?) that (maybe) should not be re-used:


Based on @FJ40Jim 's picture in post #30, it looks like I have the later bolts with the dimpled head.

My head bolts (all 15 have this head and none are tapered):

IMG_2009.JPG



So my question of course is do I have to replace these bolts or am I over-thinking this? None are damaged. My 2F was rebuilt in the early 2000s, a couple of owners ago, so it would not be that strange to see the later bolts on it. These things are expensive, and numerous.

(edited 7am)
 
Last edited:

DFXR

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OK, I am back in business. I finally have a rebuilt head and most of my reassembly parts. All of which have taken about 3 times as long to get as I expected. A little more cleanup on the block and I will be ready to start remembering where everything goes.

Question - I started chasing the head bolt holes with an M13x1.75 tap, and I'm getting a lot more resistance than I would normally get when chasing a hole. Feels like the tap is actually cutting as soon as the tapered end goes under, so I have stopped. Anyone have insight into this? I am using a standard 13x1.75 tap, not a bottoming tap or a "chase" tap, because I could not find anything special in this size.

All of the head bolts came out without too much fight, and all are in good shape - so I do not think that the holes themselves are buggered.


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NeverGiveUpYota

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What do you all use to clean up the block deck and tops of the pistons? I am thinking I would scrape the block surface (carefully) and hit it with a red scotchbrite, but what solvent, and what abrasive do I use on the pistons?
Pretty sure I used oil to soften the old gasket material. I blocked all holes w/ rags and only did a few inches at a time before using a shop vac to grab the bits.
 

DFXR

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Pretty sure I used oil to soften the old gasket material. I blocked all holes w/ rags and only did a few inches at a time before using a shop vac to grab the bits.
That’s pretty much what I have been doing, with various solvents, plus a little bit of scotchbrite (by hand and with the shop vac running next to it). Cleaning the block deck has been the biggest pain so far. The old gasket seems to have etched it in a few places.

The guy who rebuilt the head suggested running a couple quarts of cheap oil straight through (meaning into the filler and down and out of an open drain plug) to help flush any clean up gunk.

He also suggested 80 grit (!) on a big sanding block for cleaning the block surface but I did not have the stomach for that...
 

OSS

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If you're going to re-use your head bolts just screw them all into the head bolt holes in the head and feel how they go. If they screw in fine all the way to the bottom, then no worries and I wouldn't bother with a tap. For all you know it's a Chinese tap that's slightly out of spec. Who knows.

Cleaning out the female threads on the block (of rust and carbon primarily) should take no more effort than scraping teeth. If the bolts were dunked in motor oil before screwing them in to torque down the head, that oil on the threads will eventually burn off into carbon, kinda mucking up the threads. That's where a tap helps - cleaning that out.
 

DFXR

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Progress today.

Head is in, head bolts torqued.
Ugly old air rail nozzles in, keeping me humble
Heater joint in for a no-rear-heater setup
Temperature sender in
Center manifold studs in
Rocker arm assembly in, rocker bolts and studs torqued.
Valves adjusted as per FSM.

Some pics -

Head gasket -61030
Head going in on its plywood sled
Lube for the head bolts
Rocker arms in, valves adjusted

Now I just have to do everything else-

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