I just clocked 1000 miles on the hemi in my 68 GTX. It's an all new engine built from one of the cummins made blocks with stage v heads. 'Been noticing it running a little warmer. It's never boiled or puked out the overflow but running to the right of normal. I had the original 26 in radiator recored with a 3 row high efficiency core, 160 thermostat (I didn't know about high flow t stats at the time.) and I used gold coolant. I work in a new car dealership and have always thought the gold beat the old green hands down. A recent article in mopar action agreed. Anyway looking through the fill neck about every flue I can see is clogged. Scratching with a pick confirmed it is rust. Was the gold coolant a mistake, or maybe because its a new virgin block? What's a good chemical that will clean it without making a mess? It's detailed nicely and I hate to ruin the paint on the engine or anywhere else. Is there something I can run and drain the block and radiator afterward that will dissolve it? Also if I can get it clean what coolant would you run and is there a good additive to keep it clean?

I'm assuming the gold stuff is the GO5? good stuff. iirc the dexcool is the bad stuff. But I thought it was a coagulating/compatibility with other types issue not a rust issue. I would flush the block & have the rad recleaned then that'll give you time to decide on the best antifreeze (I like the good ole green) AND to investigate where the particles came from (rust or otherwise) & a course of action

Want it SUPER rust free? Buy 2 gallons of Evaporust (Harbor Freight). Get your engine warm, dump your coolant, refill with Evaporust, run until it warms up and you are 100% certain the thermostat is open. After the Evaporust has made the rounds shut off the engine and let it sit overnight. Next day, fire it up until it's warm again and TS is open. Drain the Evaporust (save it, it's reusable) and refill with your choice or coolant. Your radiator, block, and any other metal it contacts and soaks will be free of rust, stuff works amazingly well and absolutely will not harm your engine or radiator, etc.

and while you are working on that, how bout some pictures of the car??

Hope you guys can get this pic. I'm not great with moving pics around. And Scott the Evaporust sounds like the ticket. Thanks buddy!

One more... https://scontent-b.xx.fbcdn.net/hphotos-ash4/397110_3052124027899_1968616828_n.jpg

That is a beautiful car. I am sooooo jealous!

Are those 3" tti's?

Well thanks a million guys for the kind words! Lot of blood, sweat and money getting it there, and yes it's a complete TTI 3 in exhaust. I plan to get original looking oval tips on it at some point. It's a 4 speed and the Dana is carrying 4.10s at present so it's purty snappy from stoplight to stoplight!

another thing after you get it flushed use distilled water for the fill. I only use that and water wetter, but I race mine and anti-freeze is NOT a good thing to loose at WOT. I run a 2 core aluminum rad and stage VI heads, car never gets above 190* even in traffic.

Did the evaporust procedure sunday and yesterday. It definitely cleaned the cooling system and it's running cooler too, but of course the weather has been cooler also. Went back with green coolant and a pint of rust and scale inhibitor. Although Scott didn't specify it I refilled and drained the block and radiator with plain water first to rinse out all the evaporust. I'm almost certain my gauge is reading high. It went almost to the top of the normal range before the thermostat opened and it backed down to a hair past middle ways. I'm running a rally instrument cluster and the top of normal is about 230 degrees. Since I was able to stick my finger in the fill neck without scalding it at the time I doubt if it was anywhere near 230. I may try another temp sender and see if it changes.

Here's a shot of the interior. Since then I've replaced the steering wheel and added the bright pedal dress up.

Car is awesome.

Try throwing a high temp thermometer in the rad to get a real number.

Once the car is fully warmed up & thermostat opened, you can pop the cap with the engine running. Then simply stick a $5.00 meat thermometer in there & see what it's running at. Now you know what temp = what line on the factory gauge.

Check your timing to see if it is retarded. After you make sure it isn't, stop worrying and DRIVE THE CAR!

How hot is too hot? If it pukes green blood out of the radiator with a new cap, that's too hot.

Running a little to the right of center on the gauge? So what? The gauge is not a precision instrument...just drive the doggone car. You may find that it even runs cooler after a few thousand miles.

Enough with the worry!
R.

i noticed you have hose around the fuel line to from the vapor separator to the tee. is it in contact with the heater hoses? were you having issues heating the line?