Ok, i bought a rebuilt 302 out of a 74 maverick. the guy that built it said its bored .60 cam and 351 heads. I bought this in the fall and i work a ton of hours and just got it installed in my 53 ford customline. so last weekend we fired it up and it started great and i ran it for half an hour at 2300 rpm. it held great oil pressure and temperature. it sat for a week and today i got the driveshaft installed and when i started it, it started spraying antifreeze out of the exhaust. What could have happened in a week of it sitting still to make it do this. I havent torn into it yet to see whats wrong, im praying to god that its just head gaskets. but why would it run fine the first time and now as soon as i start it it starts blowing water out. Please help me out guys. This is not a roller motor. and i pulled the dipstick and it dosent seem like any water in the oil
Hopefully the headgaskets gotta check them against the heads and to the block.lotsa frustration building cars ,but one day after the fix,it is easy to forget the problems we encounter.
It's a bummer to be sure, but it's kinda pointless to guess what happened. You'll be pulling it apart shortly, and you will know what happened. Let us know, and post pics.
Are you sure it's not just condensation coming out of the tailpipes? Any time you shut your engine down the exhaust system cools and collects condensation, the next time you fire it up water comes out of the tailpipes. In cooler weather it's easier to see the water spraying out.
sounds like a head gasket didn't seat right. The heat made everything swell up and seal, and when it cooled, gaps appeared. When you started it, water ran through those gaps. Either something wasn't torqued right, cleaned right, or the heads are warped. That's the only thing I can guess.
Make sure to put the head gaskets on the right way, the holes in the end of each gasket go to the rear and the solid side goes in front. If you get it wrong it will overheat and the water will not circulate in the rear of the block.
If the oil is not milky, it's more and likely a head gasket. Rule 1 retorque the head bolts, after first time startup. I do this every time. Re torque warm it up again, as long the cylinders are not full of water, don't want to hydraulic the motor.
if those are truly 351 heads, they take larger head bolts, so you either need stepped bolts, drill out and re-tap the block or sleeve washers to align 302 sized head bolts. if 302 bolts were stuck in 351 W heads, they may not be torqued properly and loosen or blow a gasket.
Try retorqueing first-Then if you have 351 heads make sure you use the 351 gasket slight water hole difference and there is a front and rear on the gasket and many install backwards.
I believe that at least one aftermarket supplier sells a stepped stud or bolt for that application for the reasons he mentioned above. Discussion on the subject here. http://www.fordmuscleforums.com/all-ford-techboard/421966-351-heads-302-block.html
How do you know its anti-freeze?...If if it is there will be lots of whitish smoke because its going through combustion chambers to get out the exhaust..As previous stated I think its just condensation...
thank you all for your input. I know it was antifreeze cause i dont have the exhaust hooked up yet just the headers and it was green fluid spraying out. Luckily i have a hole in the floor board around the trans and saw it spraying out, and its doing this on both sides. I will check out everything and report back. this is my first build so im learning as i go.
I'd look at those intake gaskets, as mentioned, the 351 heads have different shaped water ports at the intake surface, and if you use the wrong gaskets, it'll leak pretty good
I used 351 heads on my 302.....Use the 351 gaskets for the intake and heads. Instead of spending a ton of money on stepped head bolts, use copper tubing as a sleeve to bush out to the 351 head bolt size. Claimer motor trick.....
All of these post are great suggestions and very well could be any of them,, I would also check the intake gaskets FORD changed them in 1974 I believe and they are slightly different ,,I ran in to this when installing 1974 or newer heads on a 1969 engine ,this was on a 351 W !! Good luck !!
If it happened on just one side, I would say possible a warped head. But since it happened on both sides, it has to be an issue with either the head bolts or the gaskets or both. I would lean towards the wrong bolts and them not being torqued correctly. Running the motor probably loosened things up and then the cool down really added to that. Sounds like it won't be too bad of a fix. Good luck!
I'm not sure about 351 heads but my buddy had the machine shop put screw in studs for the rocker arms on his 302 because of the high valve spring presure he was running.Anyway they went too far into a water jacket and had the same results you have.My .02 cents,best of luck.
the knowledge of users here is amazing.... i'd do the simple stuff first like re-torquing the heads & intake. my guess is that you were always leaking water into the combustion chambers but the leak got worse after the engine cooled and re-stared. generally, a slow leak will make white steam. the fact that your leak is dripping green coolant is not a good sign for a quick fix.
Not exactly on topic as far as the coolant leak but I always thought Ford 302 blocks were "thin wall" and wouldn't take a .060 overbore.
When I built my 351W headed 302, I used the special head bolts and 351W intake gaskets with 302 corks on the end. No problems ever.
I think a massive leak is a good sign. It means that something fundamently is amiss like the gasket/bolt issues others have pointed out. A little piddling leak is often harder to ferret out than a big one. Bob
Most guys that I know will only overbore .030 - then we look for a new block. There may be certain blocks that can take more - but I've not seen/heard of many of them. The early Mexican 302 blocks have much thicker main caps (like the early HiPo motors), but the overall castings themselves are not much different. Personally, I'd stick with .030 . . . blocks are a dime a dozen on these early non-Boss Fords. Oh well . . . maybe we'll spring for a Boss Block for our OT road-race mustang some day -- after we wear out the 302 roller, then the Mexican 302. Hopefully that is a WAYs out
thanks again everyone you have give me so much good info. I do know that it does have screw in studs. i was hoping to have this thing at the roundup but we will see how that works out.
i just talked to the guy that built the motor, he said it was professionally machined and was not cracked or warped. It does have the stepped bolts, but he did say that it has 302 gaskets not 351. of course he is saying that its my fault cause when he gave it to us he marked the firing order, but it was wrong cause the cam made it a 351 firing order so he is saying if we tried to start it with the 302 order we could have blown the head gasket. i call bs there. anyway no i know i need to get a 351 gasket set and tear into this son of a bitch.
You don't have to have any cylinder at top dead center..... Just tear into it and see what the problem is.......
I would put #1 up on TDC just so i wouldn't have to do it later. You don't need to, but when you turn the motor pull all the plugs out first. That way if there is water in a cylinder your not going to bend anything.
Don't know from Fords, but if you had antifreeze in the cylinders, you bretter tear it down and start over. If you don't, your looking at scuffed cylinders, broken rings, galled pistons and stuck valves.
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