170 & 225 head swap?

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olddog12

olddog12

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Im not a mechanic at all, lets start there lol.

My 225 has a broken stud in the block, manifold I believe it is, someone drilled it out but its crooked and doesn't seem to want to draw tight anymore, so wondering if I can just pull the entire head with manifold, carb everything from my 170 and pluck it on the 225 and call it a day?
 
Okay so I picked up a head gasket from Napa, and the guy at the counter said I should use this aerosol copper spray stuff on the gasket, block and head before assembly so it seals better so I grabbed that too lol, but I dont know if I need it so thought Id ask here.

Also, can I reuse the head bolts or should they be replaced? Anything else I need to know?
Ive looked for some videos on this but the net is kinda sparse on such content, Idont suppose there is a tutorial somewhere someone could point me to for more information?

Thanks guys!
 
Go a-head and do it... :D
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Using the gasket sealer may not be a good idea, it depends on the head gasket. Some should be installed with nothing. Also depending on the years involved, and whether auto or standard shift, you might have to or want to use the carb from the 225 engine and the choke t-stat. Most early 170 standard shift engines had a smaller carb the the auto or the 225 engines. Also 66 down used a different throttle linkage.
Reuse the head bolts.
 
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olddog12 said:
Okay so I picked up a head gasket from Napa, and the guy at the counter said I should use this aerosol copper spray stuff on the gasket, block and head before assembly so it seals better so I grabbed that too lol, but I dont know if I need it so thought Id ask here.

Also, can I reuse the head bolts or should they be replaced? Anything else I need to know?
Ive looked for some videos on this but the net is kinda sparse on such content, Idont suppose there is a tutorial somewhere someone could point me to for more information?

Thanks guys!
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If the head gasket is the steel shim type, yes, use the spray sealer. However, if it the MUCH more common composition style, do not use anything at all. It is very, very, VERY unlikely they gave you a steel shim gasket, as they are extremely hard to find. Post a picture of the head gasket so we can be sure to give you the correct advice.
 
Inspect all the head bolts for stretching or any damage otherwise reuse them. lightly lube the threads and underside of head of the bolt
 
i use a light coat of black rtv around the lifter galleries, just to have that piece of mind. Also Chase the threads with some lube make sure they get torqued down smooth and easy. Torque down increments leading up to the Factory torque specs.
 
Thanks for the informative replies fellas, this will certainly help me!

Here is the gasket photo. I also noticed they did not use the cone washers, I have some but am nervous about replacing them as the ones on there now are working with no leaks. Any thoughts on that?
m1.jpg
m2.jpg
m3.jpg
m4.jpg
 
Life got in the way on this project but it is the last step to getting the car on the road and i have 1 last question.

Do I use the rocker shaft & rods from the engine in the car or use the ones from the donor head Im putting on?

Thanks!
 
olddog12 said:
Life got in the way on this project but it is the last step to getting the car on the road and i have 1 last question.

Do I use the rocker shaft & rods from the engine in the car or use the ones from the donor head Im putting on?
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Probably best to use the rocker arms,and shaft, from the head you are installing. But you will need to use the pushrods from the 225 engine. The 225 pushrods are longer then the 170 pushrods.
PS: Do not throw out the 170 pushrods. They are getting hard to find. If you don't need tthem, someone probably will.
 
I got my head on last night and all torqued down, put the original rods from the 225 in and set the rocker shaft from the 170 on and got to thinking ( I tend to overthink things sometimes) these rockers are set to whatever the 170 rods/lifter were set to on the 170 and maybe they will screw something up when I bolt the rocker shaft down...maybe I should loosen all the adjuster on the shaft before I torque the shaft down and set them after that?? I'm worried I may screw a rod was my thinking.

That brings me to my next issue, setting the valves as I've never done this. I've watched EVERY video on youtube on how to do this and most are done with the engine hot/warm & running. Well I'm not sure I'm brave enough for that if I don't have to, where can i find some literature or video on doing this with the engine hot/warm and not running until I can find someone who can set them properly?
 
setting valves on one of these is NOT the big deal so many people these days make of it..... not hard to do. Crank it around and "rough set" them 0.003-0.004" "loose" and you will be close/
 
I dint think setting the valves would be so much of a problem either TBH, I have been told it was in the service manual when these cars were bought so it cant be that difficult but here I am asking questions with few replies.

Im more concerned about bolting the rocker arm shaft on from one engine to another and hurting a valve or push rod as the rocker arm is set for another engine. No one seems to know though.
 
Whenever installing rocker arms on any engine, it is always good practice, to back off the adjustment prior to installing.
However, I have removed the valve train from many engines, to change seals, or springs, etc. and just bolted the removed assembly back on as is.
 
So I finally got this done this weekend. Kinda set the valves but Im not too confident they are good, well unless it should sound like a tractor...if so she's perfect! She fired rite up so that was positive. Thanks for the help from those who commented.
PO had 2.5 liters of oil in it, although the dipstick says full it obviously has the wrong dipstick so Ive fixed that and added the 5 liters & marked the dipstick properly, that could make her sound like a tractor too as I havent started it back up since.

As I have never had a slant or drove this car I noticed when she warmed up that if you crack on the gas the revs drop almost instantly, like she dont hold any RPM at all, falls flat on its face when the accelerator is released. Is that normal?
 
olddog12 said:
As I have never had a slant or drove this car I noticed when she warmed up that if you crack on the gas the revs drop almost instantly, like she dont hold any RPM at all, falls flat on its face when the accelerator is released. Is that normal?
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No, that is not normal. It should run like a regular car.
Accelerate when you step on the gas, and return to a lower rpm when you get off the gas without stalling.

As already mentioned you can set the valves cold by adding .002 extra clearance. That's .012 on the intake and .022 on the exhaust. You must rotate the engine so the lifter is on the base circle of the cam. In other words, both valves should be closed on the cylinder you are working on. A quick check is that the pushrod should be loose and able to rotate easily with your fingers.

Have you put a timing light on it?
 
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Thank you sir. No I have not put a timing light on it, what should the timing be set at? Its a stock /6.
 
TDC is what most slant sixes are timed at. I would probably go 2-3 degrees BTDC but also listen for pinging and back it up until it stops pinging.
 
bcschief said:
TDC is what most slant sixes are timed at. I would probably go 2-3 degrees BTDC but also listen for pinging and back it up until it stops pinging.
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I beg to differ. Most slants have some initial advance reccommended. It wasn't umtil the later "emishion" years that the timing was retarded. I would suggest starting with about 5 degrees initial, and see how that works. If you get an improvement try adding a little (1-2 degrees) more initial. Keep doing that until the performance drops off, or you get ping under a heavy load. Then retard the timing a couple of degrees.
 
olddog12 said:
As I have never had a slant or drove this car I noticed when she warmed up that if you crack on the gas the revs drop almost instantly, like she dont hold any RPM at all, falls flat on its face when the accelerator is released. Is that normal?
Click to expand...

Sounds to me like the accelerator pump is bad. Do the revs pick back up after a moment or two?
 
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