What is the correct fan to radiator clearance?
- Thread starter jawbone
- Start date
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yes. Thought originally would have clearance issues based on posts I read. Was obviously not the case with my install.
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Spacer depths for non-clutch fans depended on blade width.
Should be room for a correct thermal drive clutch that is the same dimensions as a the factory unit.
Problems come when using the water pumps with the longer snout. But even then with the correct radiator there is room. With a later square top radiator, what I did was resolder the side mounts so the top tank was as far forward as possible. That gave enough room for the MP clutch and 5 blade fan. What your doing is better. Practically the same as factory. (And since then I've changed to a correct type radiator with 70 bottom tank).
Should be room for a correct thermal drive clutch that is the same dimensions as a the factory unit.
Problems come when using the water pumps with the longer snout. But even then with the correct radiator there is room. With a later square top radiator, what I did was resolder the side mounts so the top tank was as far forward as possible. That gave enough room for the MP clutch and 5 blade fan. What your doing is better. Practically the same as factory. (And since then I've changed to a correct type radiator with 70 bottom tank).
I like your thinking for your issue. Have not heard that approach before but whatever works.
What I did was order a factory spec fan clutch, Hayden 2747, to replace the low profile clutch I have just as you commented on. Your spec sheet is very interesting and has my radiator listed for manual transmission. Cost a bundle. Shroud I have forget where it came from but got it to match radiator. My fan 2863215 not sure what the pitch is. Worked hard not to have a clearance issue. Looks like I worked too hard. New clutch should improve things. I could even shim the radiator closer if need be. Seems like everyone else is going the other way. Did not want to connect and fill just to find out I have a cooling issue. Read many a post on cooling troubles. Thanks for all your input and spec sheet.
That sheet is from the '68 Plymouth Service manual. As you can see my copy is an original but you can get reprints and digital copies. its possible someone built up your radiator using a manual top and a bottom tank for an automatic. Similar idea as when Bob built my car's current radiator using a '68 top tank and a 70 bottom tank.
Well worth the effort you're putting in.
215 is the 18" with 7 2.25" pitch blades
probably should start a different thread.
Explain what you mean by ground screw.
This is the similar '67 Rally dash. Each of the illumination lamps has a ground to the casting.
The casting had a supplementary ground wire that attached to the dash panel where the radio support mounts.
I expect '68 is similar.
I have an original service manual but did not know it had that info in it. Thought you were displaying info from some special manual. Guess I should look more at it. No telling what I have missed and done things the hard way. Bob built my radiator as well from an original thus the cast iron pump. This was two fold. Pump for more clearance as well. Problem is I used the timing cover for a 70 or later. This was due to having a 70 model crank so needed some scale to time to. Could have used early timing cover but moved the other way. Was a difficult decision but do not regret it...........yet. That fan should pull some air with that pitch.
That's the screw that's stripped. Put a larger one in its place but voltage limiter still wants to come loose. Will try a star washer. Limiter must go there due to length of the +12 and output wiring. Have been careful not to over tighten. Think it was weak to begin with.
Do you mean the brown grounding wire? That's attached to a capacitor.
The IVR is inside the fuel gage.
Maybe a small thread-sert can be used.
Marked up from the 67 Supplement.
Acc = power into the regulator (about 14 volts) That's what the capacitor is connected to.
The IVR is inside the fuel gage.
Maybe a small thread-sert can be used.
Marked up from the 67 Supplement.
Acc = power into the regulator (about 14 volts) That's what the capacitor is connected to.
HemiSSDart
Dartus Interuptus
3/4" is the accepted spacing...
In your previous pic it's the ground screw for lamp left side of pic.
Thanks HemiSSDart
But I did.That's what she said...
BillGrissom
Well-Known Member
That is a very short fan clutch, like the one in my 1985 M-B 300D. For those with the opposite problem of no clearance, the M-B fan bolts to the water pump (same pilot hole diameter), plus the nylon fan is thinner. Many rodders use a 1990's Jaguar fan-clutch for tight clearance. So little clearance to the hub that owners have to ground one side of a box wrench to get it over the bolt head. In my M-B, I switched to bolts with a larger head so I can use a box wrench without fear of rounding off the head.
I would get the standard clutch to move the fan more into the shroud, for better airflow, easier access to the bolts, and less chance of whacking a finger while fussing around with engine running (and use clip-on ties). I understand the main risk of the fan being too close to the radiator is if you drive thru a deep puddle, the water can bend the blades forward to mangle the radiator. The Car Talk show mentioned that.
I would get the standard clutch to move the fan more into the shroud, for better airflow, easier access to the bolts, and less chance of whacking a finger while fussing around with engine running (and use clip-on ties). I understand the main risk of the fan being too close to the radiator is if you drive thru a deep puddle, the water can bend the blades forward to mangle the radiator. The Car Talk show mentioned that.
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Swinger 340
Well-Known Member
Not sure on the numbers of the fans, but as far as I know there are two types, one for AC, a thermostat clutch and one without AC as my 69' 340, Dart has, without AC. I would think the AC one should be set a given distance to record the heat and the non-thermostat one, set a couple inches from the radiator, with the blade just to the outside of the shroud, so to grab as much air as possible thru the radiator. To close it would pull most air from the center.
harrisonm
Well-Known Member
That is EXACTLY what I was going to say. You beat me to it. And you are exactly right!
Thanks BillGrissom. New clutch is on. I'm about 1 3/4 in away. Will see how it goes but will need to wait for summer to return. Thanks for your response.
Installed standard Hayden clutch #2747. Got the fan inside the shroud but only 1/2 in. I'm about 1 3/4 in away from radiator with fan.
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