620 Radiator Help: 200sx Alternator hitting lower radiator hose

[Kirden]

So I'm swapping to a 75-78 radiator on my 74 620. The radiator is wider so I haven't completely mounted it yet, but I noticed that the lower radiator hose it extremely close to the metal blades on my 200sx alternator if I use the drivers side mounting holes. It hit's the blades if I use the passenger side mounting holes.. The 75 radiator inlet is straight, not at an angle like the 74 and 521 radiators. The alternator is tighetened down so that there is barely any slack in the belt as it should be, but this alternator is a little larger than the stock one. Any tips on the best remedy for this? I thought of trimming the lower hose at the inlet which would move the bend closer to the radiator, but I would like to know what everyone thinks.

 

 

It's hitting right at the bend.

[datzenmike]

Some (510/521???) rads had a right angle on the lower output of the rad. I've unsoldered an inlet pipe before and replaced it. It's all in the snug fit and tinning preparation that makes for a good job. Try a rad shop for one of these angled pipes.

 

On my 620 I used a Z car lower inlet pipe to the timing cover above the alternator. It's angles differently than the 4 cylinder one and moves the pipe up out of the way. This allows the alternator to use a shorter belt and be lifted up away from the lower hose slightly.

[]2eDeYe]

Yep, get the Z-car inlet :)

[Kirden]

Can't make those changes to the radiator though, this is one of those crappy replacements with plastic tanks. It's temporary until I can get a proper aluminum radiator. I might toss out the whole idea and just stick with the crappy radiator I had until I get the aluminum one. The issue was that with that radiator I can't run a thermo because it is a single core POS and it will over heat, but atleast I could drive the truck.

[Kirden]

Well, not really happy about it, but I am sticking with the horrible single core radiator I had for now. Gonna see if I can get a refund for the plastic tank radiator so that I can order an aluminum one. Thanks for the ideas though. If I can run across real 74 radiator that would be perfect for now.

 

We were able to fix the upper radiator hose on the single core though, so I shouldn't have any overheating issues anymore.

[banzai510(hainz)]

didnt no the 620 rads cam in the plastic type

[ggzilla]

Or aluminum.

 

Why not fit the 240SX aluminum rad? There's enough space and under $100

[ggzilla]

You could also fit an original style 620 alternator, which is one inch smaller diameter. The 1979 version is Internally Regulated.

[Kirden]

The radiator I have in the truck now was there from the previous owner. it's a single core peice of crap. The replacement radiator was an auto zone special, plastic tanks and aluminum core for 75-79 620s. 

 

The 240sx option is interesting, I'll look into that. I would really like to get either an aluminum one made to fit the 74 620, or get a 74 620 radiator and have it rodded out. The goal is to cool a 2.2l stroker.

 

I'll also look into the 79 alternator. I got the 200sx one because my alt went out and that's what was available. Do you happen to know the amps on the 79? I have a decent sound system (200 watt amp, single 10" sub, 2 5.25s and 2 tweeters) and will be running LEDs for the dash and higher output headlights so I want to make sure my charging system is up to the task. 

[ggzilla]

620 use 35A alternators except AC models used 38A units.

 

LEDs use less energy, but with the amp and high output headlights stick with a 60A unit.

[Kirden]

Thanks gg, a fountain of knowledge as always :)

 

I am looking into the saturn alternator swap now, that will get rid of the metal finned fan and it is smaller than the 200sx unit. Just need to come up with a bracket. Bonvo has a really good write up on it and those are 105 amp units.