Slant six swap HELP!

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bamacuda

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Greetings-
I’ve been away for a while.
I have a question about a slant six swap. I have a friend with a 65 Valiant with I suppose a 225 with 904 trans. This motor overheats and he wants to replace it. I have a low mileage 170 (2463230-9) and three speed manual out of an A100 van.
1)Will this motor mount to the 904?
2)Will the oil pan and oil pickup transfer over from the 225 to the 170?
3)Will the throttle and kick-down linkage transfer over to the 170?
4)What other factors do we need to address?
Thanks guys and gals for any and all help and info.
 
If you're swapping the whole motor over, then the only thing that would really matter is the exhaust and the kickdown linkage. The deck on the 170 is a little shorter than the 225. Trans Bolt patterns are the same, the 225 pan should fit the 170 but there's only one way to find out for sure. Double check that that even needs to be done, the pan that's on the 170 now might just fit fine
 
You need to make sire the 170 is not the different size crank register. The later ones changed crank register size. I think the 170 was made through 69 so that could be an issue I think.

@Charrlie_S or @slantsixdan can tell us for sure.
 
Thanks.
I was just under the assumption that trucks vs cars had the sump in different places in the oil pan as in rear sump vs center sump. I will look closely at the engine that is coming out.
What will be different about the exhaust?
What will be different about the linkage? Do I need to put all the linkage from the 225 onto the 170?
 
This motor overheats and he wants to replace it.

Bit of a long leap…why not diagnose the problem first? Overheating is usually not due to something that would warrant replacing the engine. If the engine is worn out or otherwise faulty and overheating, that's another matter. But what if the overheating's due to, say, a bum radiator? Then all the hassle and sweat of an engine swap will be for nothing; the new engine will overheat, too.

I have a low mileage 170 (2463230-9) and three speed manual out of an A100 van.
1)Will this motor mount to the 904?

Yes.

2)Will the oil pan and oil pickup transfer over from the 225 to the 170?

Yes, and you will need to make that swap. Take the opportunity to service the oil pressure relief valve to make sure it's doing its job, as described in these two threads: thread 1, thread 2.

3)Will the throttle and kick-down linkage transfer over to the 170?

Yes, though you may need to shorten and rethread the rod that runs down from the throttle bellcrank in front of the firewall to the kickdown pivot at the front of the floorpan. Even if not, that rod will need adjusting to achieve correct shift points.

4)What other factors do we need to address?

Not many, really. Exhaust headpipe will be lowered by about an inch when going from a 225 to a 170, which may or may not make any practical issue. Engine mounts are the same.
 
Dan, he tells me he has had the radiator completely reworked, changed the water pump, thermostat, all hoses, flushed it several times, and he still gets overheating. Tune up shows timing is right.
He says he can feel it warm up, the thermostat open, plenty of water flow in the hoses. Still overheats.
What else could it be

Bit of a long leap…why not diagnose the problem first? Overheating is usually not due to something that would warrant replacing the engine. If the engine is worn out or otherwise faulty and overheating, that's another matter. But what if the overheating's due to, say, a bum radiator? Then all the hassle and sweat of an engine swap will be for nothing; the new engine will overheat, too.



Yes.



Yes, and you will need to make that swap. Take the opportunity to service the oil pressure relief valve to make sure it's doing its job, as described in these two threads: thread 1, thread 2.



Yes, though you may need to shorten and rethread the rod that runs down from the throttle bellcrank in front of the firewall to the kickdown pivot at the front of the floorpan. Even if not, that rod will need adjusting to achieve correct shift points.



Not many, really. Exhaust headpipe will be lowered by about an inch when going from a 225 to a 170, which may or may not make any practical issue. Engine mounts are the same.
Dan,
 
Does it FEEL hot? Has he checked it with a heat gun? Verified it?
 
he still gets overheating

Defined how? If it's just the dash gauge moves toward "H", that could be a gauge/sender issue, pretty easy to fix. If it's pinging and boilover and fountains of steam, actual signs of real overheating, when does it happen? High speed on the highway? Low/no speed stuck in traffic? Doesn't matter/always?

What else could it be

Assuming it's actual overheating and his radiator work was adequate and he's made sure his new thermostat isn't faulty, it could be mud/rust accumulation in the block (this takes more than just pouring in a bottle of fast flush, but doesn't require pulling the engine), could be exhaust backpressure (internally collapsed muffler, krunched pipe, manifold heat control valve stuck "on"), could be radiator fan installed the wrong way round. Could be lean fuel mixture. Could still be wrong ignition timing—the crank pulley is a 2-piece item, with the outer ring (w/timing mark) rubber-bonded to the central hub. Over the years that bond can let go, then the ring slips relative to the hub under the drive belt torque load, so the ignition timing mark is no longer accurate. Checking for this requires verifying TDC (between compression and power strokes/both valves closed) in № 1 cylinder corresponds to "0" timing indication.
 
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Fix the overheating issue, trust me you dont wanna down grade to a 170. What kind of fan is on there? is the fan pulling a lot of air thru the radiator? Also check the fan rotation direction. But first i would start with a compression test a best
 
Thanks Man. I will have a lengthy conversation with him to determine if any of these are it.
You guys are awesome!

Fix the overheating issue, trust me you dont wanna down grade to a 170. What kind of fan is on there? is the fan pulling a lot of air thru the radiator? Also check the fan rotation direction. But first i would start with a compression test a best
 
I just diagnosed my overheating issue.. bad head gasket.. Does not warrant an engine replacement!
 
I just diagnosed my overheating issue.. bad head gasket.. Does not warrant an engine replacement!

I agree with you 100% but some people just don't think like that. I had a friend years ago that if he had a valve cover gasket leak, off to the dealer it went to get traded. If it didn't have decent trade in value, he'd put an engine in it. No I'm not exaggerating. That's just how his mind worked........or didn't work.
 
I agree with you 100% but some people just don't think like that. I had a friend years ago that if he had a valve cover gasket leak, off to the dealer it went to get traded. If it didn't have decent trade in value, he'd put an engine in it. No I'm not exaggerating. That's just how his mind worked........or didn't work.

I know a guy that would buy a new truck, when it needed new tires he would trade it in
 
In this situation, the driver is still driving it daily to work. Looking to repair it in one day. If it’s a head gasket, probably can get it done in one day. If there is a cracked or warped head or block, we’d be out of luck.
 
In this situation, the driver is still driving it daily to work. Looking to repair it in one day. If it’s a head gasket, probably can get it done in one day. If there is a cracked or warped head or block, we’d be out of luck.

What if, on the off chance, since it has not been diagnosed, if you install the other engine and it still overheats since you don;t know what the problem is? Essentially, since yall are not diagnosing it, you are just throwing parts at it. People rarely fix cars in that way.
 
Good question.
I am going off what is his diagnosis. I have given him a systematic list of how I would diagnose and narrow down the cause or causes of overheating. He bought the 170 to have as a backup. I inquired so if that is the determination, to replace, that we would be ready to do it without surprises.
I haven’t seen the car in question, but when I do, I will assist him in diagnosing the root cause. Thanks to all of y’all for your input. Feel free to keep sharing as it is possible that it is one or more of these or even something else completely.

What if, on the off chance, since it has not been diagnosed, if you install the other engine and it still overheats since you don;t know what the problem is? Essentially, since yall are not diagnosing it, you are just throwing parts at it. People rarely fix cars in that way.
 
Good question.
I am going off what is his diagnosis. I have given him a systematic list of how I would diagnose and narrow down the cause or causes of overheating. He bought the 170 to have as a backup. I inquired so if that is the determination, to replace, that we would be ready to do it without surprises.
I haven’t seen the car in question, but when I do, I will assist him in diagnosing the root cause. Thanks to all of y’all for your input. Feel free to keep sharing as it is possible that it is one or more of these or even something else completely.

Well good luck with it! I do hope it works out one way or the other.
 
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