www.ColoradoClassicBroncos.com

So since I've taken a break from the 427 build for a bit, I thought I'd work on some "cheaper" projects and # one on the list was the leaky head gaskets on my OEM '70 302. For 42 years old and 110K miles, it's running ok...but it s black crap and water out the exhaust, smells like gas, and leaks all over the block.

So last weekend I dove into it and tore it all apart. I had to remove the air cleaner, carb, intake manifold, power steering bracket, alternator bracket, all the hoses, and exhaust manifolds. That got me to the heads. First lesson was it's probably a good idea to put it up on stands and drain out all the coolant I could....when you crack the seal on the heads....all the extra coolant runs out...all over everything...including into the cylinders.

After removing the heads I realized I couldn't just put them back on again (well I could but you know). So after some research on re-manufactured heads from the local parts shops, I dropped them off with Scott at MPG Heads in Englewood. He's going to clean them up and rebuild including valve seats for unleaded gas. I also dropped off the intake manifold...he's going to hot tank it and reseal the plate on the underside.

I spent a good couple hours cleaning up the block and mating surfaces where the heads go. There was quite a lot of crap from the leakage.

Turns out that most of the gaskets I got in the kit for the 427 that I'm not going to be using will work fine on the 302. Scott said it will take about 10 days for turn around on the heads so I'm really at a stand still right now.

If you dont mind me asking, what is it going to cost to get the heads and manifold done? iam doing the exact same thing here soon and will be refreshing the stock 302. However seeing how i dont have 427 to swap in eventually I was contemplating beefing the 302 up a bit with new heads, cam etc etc...

$280 total. But I don't think that includes any "extras" they may find when they tear them down. Also, keep your eyes on Craigslist. There are 2 rebuilt sets on there now for $125! Both are sold already.

Manifold is $60 to crack open and hot tank.

cool deal, iam on there everyday.. entertaining the thought of upgrading the heads since iam going to have the engine out and tore down... we will see, still working on cleaning the damn body panels.

I would suggest new valve springs if your not doing them in your plan.

zillacon wrote:

landshark wrote:cool deal, iam on there everyday.. entertaining the thought of upgrading the heads since iam going to have the engine out and tore down... we will see, still working on cleaning the damn body panels.

I know you have a lot on your plate with your resto but if you want to rebuild heads yourself and save some bones I will borrow you the tools. I would also do the timing chain and gear while you are in there if you do the heads. Some of the 302 timing gears are made of plastic and with 100K the chain will have some stretch so it is cheap insurance. If you go to the breakfast we can talk some more.

I really wanted to do it myself also but then thought about valve seats needing to be replaced and that threw me off. Sounds like a good deal though if they don't need replacing.

Where does the gasket go for the carb? Between the manifold and spacer or spacer and carb?

airbur wrote:Where does the gasket go for the carb? Between the manifold and spacer or spacer and carb?

Should be one for each.

Viperwolf1 wrote:

airbur wrote:Where does the gasket go for the carb? Between the manifold and spacer or spacer and carb?

Should be one for each.

I had a feeling that was the case! I've only had one in there:) No wonder I always smelled like fuel.

zillacon wrote:Some of the 302 timing gears are made of plastic and with 100K the chain will have some stretch so it is cheap insurance.

Funny you say that. I didn't have the time to rebuild my engine when I needed to, but when I had it done, I dropped it off to the guy who did the work & it wouldn't start again for him. He popped the timing cover off and the plastic timing gear was so worn that it was down to the aluminum spokes, the chain was stretched out so much that he lifted it off. But that was after I had turned the speedo over twice and the PO did it once.

If you're looking for "stock" heads (not aftermarket), '69 and '70 stock heads flow the best till you get up to the GT 40 series... make sure the early head's seats are changed out to hardened seats

Get these early heads ported and they do flow quite well.

Thanks for the info. I'm having the heads rebuilt...same shop that did my cam and the windage tray. They should be done next week sometime. I'll a coat of paint on them and re-install.

Spent a few hours today degreasing all the bolts, rockers, pushrods, and nuts. That crap was caked on there. I had saved the gallon of carb cleaner I bought for that rebuild and used it. Did a pretty good job on everything. I did notice that there is some wear on the rockers where the pushrod seats. After looking up prices on replacement units...$10 each!....I decided to just use the old ones. The lifters are in amazingly good condition as are the pushrods.

Since you pulled the lifters did you note which cylinder they came from? Need to match them back to the original lobe they were on.

Yea...I only pulled 2 of them so far and am keeping track.

Found a new supplier for Mustang/Bronco engine parts since no one around here carries the right water inlet elbow. http://www.restoremustangs.com They have everything and decent prices/shipping also. I ordered the elbow, a new temp sending unit, and a new pvc grommet for the valve covers.

zillacon wrote:

Booger wrote:Since you pulled the lifters did you note which cylinder they came from? Need to match them back to the original lobe they were on.

Yuppers, I like to note location of rockers and push rods as well. That will eat up a Cam in no time flat!

I was gonna make mention of that but with the valve job they may grind the valve tip so the rocker will not contact the same.

Booger wrote:I was gonna make mention of that but with the valve job they may grind the valve tip so the rocker will not contact the same.

Exactly. A new set of rockers would be best but these are fine and will keep me on the road even unmatched to their old counterparts.

Today I was tinkering around and noticed that the thermostat was stuck to the housing...so I pried a little and heard the wonderful sound of yet MORE coolant all over my garage floor:) I quickly stuck it back on.

Also drained out all the old oil and ran a few quarts of new stuff through it until most was clear. Also tossed the oil filter.

I'm so happy your doing this. Keep it updated as I'm doing the exact same thing and have never tackled this portion of a build.

Since I'm leaving this engine in would I be best to go ahead and replace the rockers and other bits? Going to take the heads in to get looked etc.

landshark wrote:I'm so happy your doing this. Keep it updated as I'm doing the exact same thing and have never tackled this portion of a build.

Since I'm leaving this engine in would I be best to go ahead and replace the rockers and other bits? Going to take the heads in to get looked etc.

You don't have to replace them. Clean the old ones and check em over for excessive wear. Same goes with the pushrods.

Made a little more progress. I pulled the lower hose from the radiator and drained out all the rest of the coolant (do that first!). Cleaned up the mess then checked over all the lifters, cleaned them up, re-oiled and re-installed. Stopped by Ace and picked up a 3/8s plug for the intake manifold's rear vacuum port that I'm no longer using.

Heres a pic of the intake parts I'm replacing....heater inlet elbow, temp sender, an using a plug for the vacuum port.

Couple parts from Orielly.....had to order in a new thermostat and 1 more carb gasket.

Called to check on my heads today and Scott was putting the finishing touches on them. Turns out they were in good condition...all the valves were good and I decided to reuse the springs also. Should be able to pick them up tomorrow :)

Yesterday I picked up some more coolant along with a new thermostat. I also picked up some Seafoam to run through the engine after I get it all back together.

Not to hijack but I have my old heads of my 71 if somebody wants them.

B.O.B. wrote:Not to hijack but I have my old heads of my 71 if somebody wants them.

Nice! Are they rebuilt? I'm sure someone would be interested.

B.O.B. wrote:Not to hijack but I have my old heads of my 71 if somebody wants them.

i might be interested if they are rebuilt and have injection ports for emissions? i assume i can just take out some freeze plugs for that though.. unsure..

Picked up the heads.....they are purdy:)

Little paint.....

Heads on and thread sealing...

your making good progress