Dirtbox Venom mini-buggy upgrade/rebuild!

[fowler]

Why not mount the tank either on the same bar as the rad or in that triangle to the left of the bush

The tank needs to be the same level as the rad

 

[mysteryboy28]

the tank is part of the oil reservoir connected to the oil pump. so relocating isn't exactly gonna work.

however, i have found a solution. i'm gonna bypass the tank altogether (gotta find some 1" elbow and T connector adapters. supposedly i can use copper pipe adapters from the hardware store, just rough em up a bit with sandpaper on the outside to keep the hose from sliding off), and use a overflow recovery tank ($9 at o'reilly auto parts). the overflow tank CAN be mounted below the radiator (lots of reading of success stories to confirm this). the tank has a pinhole vented cap , and nipple on the bottom of the tank that you connect a tube running to the overflow nipple at the top of the radiator. piece of cake.

edit: just had o'reilly place a 24 hour order, will be in tomorrow morning. they're gonna price match advance auto, getting it for $7.99. woo-hoo!

 

[jamyers]

That sounds good! Main point of an overflow tank is to keep the radiator full of coolant as it expands and contracts. Old cars that didn't use them were typically designed with a downflow radiator with a large upper radiator tank and no overflow tank - and it was normal to remove the cap on a cold engine and have the coolant level 1-2 inched below the top. On modern systems, the coolant tank is a place for the extra expanded coolant to go when the engine is warm, and then get sucked back into the system when it cools.

Don't want to sound like I'm talking down to anybody, but it pays to keep the basics in mind. (like "air goes up", collant goes down" when thinking about burping the system - it's a good idea if you can to route hoses to air will naturally go to the top of the system and it'll burp itself easily.)

 

[mysteryboy28]

after hunting extensively around town, i have not been able to find any tee fittings that can handle the 180+ degrees that the cooling system will generate. the copper elbows they have at the hardware store don't have enough surface area for the hose to really slide on and grab on to. so... i'm going to keep the sled reservoir in the mix with the existing hose connectors, seal off the overflow nipple by melting it with a lighter, and hope that the sled radiator cap won't open up and relieve pressure by oozing coolant when it gets hot. if it does, then i will find a solid cap of some sort to replace it with.

picked up the new reservoir, wishing it was warmer out! once i get the cooling system done i can focus on the fuel delivery (put the 1/4" barb on the tank, rinse it out good with some gas, add the new fuel filter and hook it up to the fuel pump), basic electrical, throttle cable, throw in a seat - then i might be ready for a test drive!

 

[jamyers]

I've made coolant-hose connectors out of galvanized pipe short-nipples, elbows and tees. Works well, but not as lightweight as copper tubing would be...

Then again, since the tank is part of something else and it's staying, capping it off will work too. Instead of melting it, I think I'd clamp a short piece of hose with a plug (bolt) in the end to cap it off - less permanent and prolly more reliable.
As long as the cap on the tank has a higher pressure rating than the one on the radiator, any venting will go out the lower-rated radiator cap. Better yet, find a cap that'll screw down solid (might have to mod one) and you won't have to worry about anything coming or going through it.

 

[mysteryboy28]

sled cap is rated for .9 bar, and the honda radiator cap is rated for 1.1 bar. sooo... i'm hoping that by capping off the sled overflow hose that it'll be enough to keep coolant from leaking there, and that all excess pressure will properly be routed to the radiator overflow hose... maybe? lol.

 

[jamyers]

hmm...yeah, that oughta work! With the sled overflow blocked, its caps top sealing gasket would have to fail for anything to get out.

 

[mysteryboy28]

got the new overflow tank mounted, and made a mount for the fuel primer pump (the alternative to a choke. just reach between the seats and pump a few times, then turn the key!). had to try a few different radiator caps before the lady at O'Reilly and i agreed that the radiator needed to have a couple of small edges filed down on the spout to accomodate the right cap.

got all the hoses hooked back up and it dawned on me that the extra openings/connectors on the front/bottom of radiator were for cooling lines for an automatic transmission. so now i gotta find caps for those openings. luckily i had a nut in my collection of nuts and bolts that was the same size as the thread on those connections, so i can just take the nut up to the hardware store and find the right size caps.

screwed on the 1/4" fuel barb on the tank, added some pre-mix gas i had sitting around, and swished and dumped a couple of times. connected the fuel filter to the fuel line, cut the line to length, and connected the gas tank.

today i'll get the transmission line caps for the radiator, study the wiring diagrams so i have a realistic idea of how to approach the electric/wiring, and then hopefully get back out to garage and see if we can get her fired up before morning, or blow myself up trying!

 

[mysteryboy28]

big question for the radiator experts: is it ok to suck from the top of the radiator, rather than the bottom? i just came across the flow chart for the cooling system, and the way it's hooked up now it's sucking from the top of the radiator and pushing from the bottom. i'd imagine that as long as the radiator was kept full this would be ok, but wanted to get an educated opinion. to change it now would be a pain in the @$$. does gravity make it harder for the coolant to get pushed to the top? i dunno... thanks.

 

[jamyers]

You REALLY want the engine to get its coolant from the bottom of the radiator - just too risky to draw from the top, if you're the least bit low you can meltdown the engine while having plenty of available coolant.

The trans cooler in the rad shouldn't need high-pressure caps on its fittings, it's basically just a tube inside the radiator. You could leave it uncapped no problem, but around here it'd end up full of mud-daubers.

 

[mysteryboy28]

yeah i just read somewhere that it was common that the transmission lines were just connected to a coil inside, so no caps were needed. good thing, cuz i couldn't find 10mm pipe thread fittings at either the auto parts store or home depot, which is what carquest said i needed (and said was an odd size that would be hard to find). i had ran up to home depot and bought the closest size i could find, thinking i could use some gasket maker sealant on them, but even those 1/4" brass caps wouldn't thread on more than a 1/4 of a turn. wasn't going to force them.

so... on to my dilema of the radiator hoses. to hook things up properly i'm going to need an elbow or 2, and the only ones i can get in town are like $7 a piece. ugh. not to mention the tee or Y piece i need that ISN'T available in town. the buggy is already nickle and diming me to death. lol. thinking...

would it be bad (and i kind of know better than to ask, lol) to make my own fittings from steel tube? doesn't the coolant have anti-rust properties?

 

[fowler]

Yes some coolant has anti corrosive chemicals

If u can't find the correct caps but have bolts that do fit then why not put bolts in there

 

[mysteryboy28]

the holes aren't threaded, just the outside. i'm not worried about that anymore, since i now know that the coolant won't pour out of the transmission line holes. if i find some plasic caps to throw on to keep dirt and bugs out, then cool.

biggest concern now is getting the hoses routed properly. the motor has 3 hose connections: 2 in the back flowing out, and 1 in front under the exaust header sucking in. the sled reservoir is currently acting as a tee for 3 hoses, and poses the problem of possibly leaking because the cap is rated for lower pressure than the radiator cap, and that's the main thing i need to eliminate. then it's a matter of getting the hoses pointed in the right directions without crimping. so the elbows and tee are a bit pricey and the tee is hard to find. there has to be a simple cost-effective solution...

 

[fowler]

What diameter is the hoses

I've heard of people using those big pipe door handles
Like the ones on flash shop doors

They are stainless steel and u can cut them to the required angle
They got them from the wreckers for real cheap

 

[mysteryboy28]

hoses are 1 inch inner diameter. i think i know what you're talking about with the tube door handles. although i don't think it's going to be easy to find, and that doesn't solve my issue of needing a tee/Y adapter.

i have determined that a tee won't work, and that i need a Y fitting because i will be combining the dual outputs on the rear of the motor into one to feed to the top of the radiator (with 2 elbows). then i will run a hose with 3 elbows from the front of the motor to the lower radiator connection. so i need a Y and 5 elbows to get 'er done.

the antifreeze i bought says "•Provides maximum protection against scale, rust, corrosion, freeze-up and boil-over"

so do you think it might be safe to use regular steel tube for the fittings? i could whip up a "Y" and some some elbows.

 

[fowler]

Well all the heavy deisel equipment uses untreated steel pipes so it should be ok

Not to mention of course the steel blocks


Just make sure there is no ristorante scale in the pipe

And make sure the wall thickness isn't too thick as to not impeed coolant flow

 

[jamyers]

I've used galvanized iron pipe with no problems on my '62 Ranchero for years - go for it!

 

[jamyers]

Question - is there a water pump on the engine?

 

[fowler]

Glav

Never thought of that

As long as the glav won't peel off and go though the system

 

[mysteryboy28]

radiator hooked up. now to fill 'er up and check for leaks!

i ended up using the existing sled radiator hose for the elbows, only had to fab up the Y connector, and then use a couple of straight pieces of tube.