I have a 46 Merc convertible I am building. I put a Ford 302 from a 1978 ford truck into this project with a C4. Got is started up and drove it and it overheated/boiled. I drove it again and watched the oil pressure drop to zero after a few minutes. Pulled the oil pan. The bearings were shot. Had my local garage drop a Jasper replacement into my car. Same 1978 ford 302. I bought a long block, heads were installed by Jasper. Seals are installed the correct direction. Drove it home. 5 miles. Overheated/boiled again. It has a Edelbrock 289 Perfpormer intake with rear water ports blocked. I have a Champion aluminum radiator with no leaks. Installed a 1978 Ford radiator cap on because Champion plastic one sucked. I have an aluminum overflow tank. The fan is a Summit racing pusher fan. From the front of the water pump to the back of the radiator is only a half of an inch so no room for the water pump mounted fan or a puller fan. I put a new heavy duty Duralast water pump on. Still overheats. I put upper and lower radiator hoses on with internal springs to prevent collapse. Still overheats. I have put in 2 thermostats, a 160 and a 180 with the spring end of the thermostat pointing back towards the firewall. Still overheats. The intake gaskets for the 1978 motor have slight restrictions in the front water port area. Older 1968 era intake gaskets were open squares. It has 1978 intake gaskets installed. Where do I look? I refuse to believe a motor with 15 miles on it has a bad cylinder head and it did this overheating before we replaced the motor. Engine is new. Water pump is new. Thermostat is new. Radiator is new. Fan is coming on at 160 degrees. Only thing I haven't replaced is the intake and/or gaskets. I am at my wits end. Suggestions and or guidance would be a wonderful thing.
Have a radiator shop check the cooling system for exhaust gases.If none that would rule out a crack.How close is the fan to radiator? if set back you may need a shroud to pull air throught.
Very similar power plant to my 53. For years I had a 55 radiator without a shroud. Did great as long as I didn't encounter traffic. I bought a universal fit radiator and fan with shroud kit, that was dimensionally close to the original. Now all is well.
Are you sure you have the right water pump and not one for a serpentine belt equipped car? What do you consider overheating temperature wise? Is it just puking out coolant because you have overfilled the radiator?
I posted on the other thread you posted this morning but J.A. makes a valid point, if the water pump is indeed a serpentine type you would definitely have overheating problems. HRP
Based solely on your information, I would suspect the heads. They were over heated on the first engine..... and then put on the second engine. Are you sure they were checked for cracks?Are you sure that the head gaskets were installed correctly? Bones
302 in my 29 did that until I flushed the engine , Radiator water looked good , when I flushed the engine the water was muddy brown . problem solved
have you burped it? when I worked in a ford dealership in the 80's it was common for late 70's early 80's 302 to have an air pocket trapped in the motor after changing thermostat, hose, or water pump etc. We would raise the front of the car up as high as we could using a bumper lift. Fill the radiator with coolant, start the car and wait till the thermostat opened. Then the air would burp out the radiator and you could fill it up and it would work properly. Not doing it meant a come back with an overheated car. Not sure this is your problem but not hard to do.
Yeah, I'd be suspicious of the water pump also. Does your timing cover have the mount for the mechanical fuel pump, or is that boss missing? You are running a V-belt system, right? How big is your radiator? And truthfully, I'd move the radiator forward to allow room for a mechanical fan and shroud. Shouldn't be a big deal with the Mercury's longer front end compared to a Ford. One thing I always do on my Fords is drill a small (one 1/8" or several 1/16") hole or holes in the thermostat flange to allow trapped air to escape when filling the cooling system. This has no detrimental effect on the t-stat operation and usually eliminates the 'burping' issue.
Look for dumb stuff, dumb stuff like factory packaging/shipping caps stuck down in the radiator inlet/outlets. This happened not too long ago on here.....drove the guy nuts. Another fellow claimed his new radiator was nearly stopped up with glue at the bottom tank. My advice is to pull the radiator, use a hose pipe ( garden hose) and see how much water flows through it. I have never had a problem with a SBF (302) running hot. As a matter of fact I consider them a cool running engine. Much much cooler than say a flathead or FE. What am I doing right? My F1.... I am using the original flathead radiator and in the V8 location. High profile valve covers get into the firewall. Factory style 289/302s clear fine. It's mated to the 1950 transmission. I say this because a SBF with a mechanical fan should fit in a Early V8 vehicle. F1 is not that much different than a 46 Ford/Merc car. Note I said V8 position. The longer 7HA six was offered with these cars. You can move the radiator up to the six location to gain some clearance. If you have mounted the engine (302) more forward than a flathead V8, you may already be in the six location. If your car is heavily modified here.....same deal, you may not have that adjustability. I'm using the 1950 V8 radiator. If my old battered radiator was at swap meet, it would not bring 5 bucks. Somebody has cut the top left inlet off and patched it with some kind of epoxy. The top tank seam is leaky. A flathead or 302 fan has kissed the core leaving a partial fan print in the fins. All in all, it's a piece of junk. But.....it's a piece of junk that has always cooled the engine and cooled it very well. My engine is a '68 302, very similar to yours. Here's the big question..... Why does my old junky (but original to the vehicle) stuff cool the engine fine yet your new stuff( aftermarket) does.....not? Maybe there's an engine problem? What can cause an engine to run hot? What's the deal about blocking off rear coolant passages on the intake? Head gasket....cracks....warps and leaks..... Does it steam out of the exhaust? Does the coolant smell of gasoline? Do you loose water.....blow it out? Do you blow water out the cap when you rev the engine? Is the engine block full of goo? Since you had a similar problem with the old engine.... What is the common denominator? You re-used the heads right? You are using the same radiator right? Since 2 engines have had the same problem..... What's left.....? Examine the radiator as said above....flow some water through it. Flush the block. Do a compression check. Water pump rotation as mentioned. Is the radiator too small? My flathead radiator is giagantic especially compared to say a Fairlane or Mustang radiator. With this said.....those tiny radiators cooled those SBF cars fine. Think it through and like I said in my opening sentence..... Look for dumb off the wall stuff. That stuff can be eliminated by flowing some water through it.....and doing more checks.
Could it be a later model water pump you have on there? Not sure if they bolt up or not, but the '85 and up water pumps are reverse rotation. That would cause some issues!
I thought it might be a reverse water pump too. The new water pump is for the clockwise standard rotation v belt setup I am running, not a serpentine as I suspected it might be. The heads are the new heads that came from Jasper, not the old heads that were on the original motor. The new heads were part of the long block I bought. The motor has 15 miles on it, so I can't imagine it would be gunked up. The radiator is for a 1946 - 1948 Ford (Mercury). I reused that from the original. Only that and the intake are the same between the original motor and the new one. I plan to pull the intake tomorrow and put new gaskets on it. I also have a manifold that has the rear coolant pass through between the back heads. When I drain it, I will flush the radiator and see how much coolant passes through it. Water doesn't blow out the top of the radiator when hot. I get steam coming out the top of the little vent hole. when I park it. It also sounds like a tea kettle bubbling when I park it. The fan is a 16 inch 1600 cfm. I did not burp the engine. I suspected I might need to do that.
There must be more room in your F1 compartment. The standard bugaboo with using a SBF in a swap is the length. I don't know about Mercury, but one won't clear the stock radiator in a 42-48 Ford originally equipped with a V8 with the radiator in the stock location. The radiator in my avatar was pushed forward by about 4" (which caused other issues) to gain the needed clearance. The same-year Mercurys are longer from the firewall forward, so I would assume there should be plenty of room to move the radiator. I did a 351W swap into a '56 Ford, and by NOT using the 'standard' late Mustang motor mounts that everybody else uses but instead custom-built ones to move the motor as far back as possible, I was just able to install a mechanical fan without relocating the V8 radiator.
Radiator is brand new. I pulled the intake. It is an older Edelbrock Performer with the rear water passage. I drained the coolant. The passenger side water ports in the heads have no antifreeze showing. The rear driver side port to the intake still had antifreeze in the cylinder head up to where the intake was while the front water port on the drivers side did not. Does that mean a blockage in the cylinder head or is this normal? Charlietruck62 said to burp the car by lifting the front end. I was going to do that after putting the whole thing back together but I am paranoid at this point that still seeing the fluid that high in only the one port means something bad....
On some Fords you can put the head gasket on backwards & it screws up the water flow. A friend did that on his roadster. His was a 351.
Yep, this will do it. Had a friend just recently that had overheating issues after doing a valve job, one head gasket was backwards. On a SBF, when you pull the intake look down the front water passage in the head. If you see an opening into the block, the gasket is backwards.
The front water passage has a little coolant left in it. The back of the motor sits a little lower than the front. It's as if the drivers side as a whole still has coolant in it. Jasper installed the heads. Where would the hole be to see if the gasket is backwards. On the deck by the block?
I am looking down the water intake port of the head on the front of the motor. There is still fluid in it too. Not as much as in the back, but the motor tips up slightly. Passenger side is dry
Just pay attention to the embossed "Front" on the head gasket. When done right, it looks like one gasket is on upside down compared to the other. SPark
Haven't done a small block for a while, but on an FE you can tell from the outside, there's a tab you can see at the front if it's on correctly. If people would just follow directions, FRONT is clearly stamped into the gaskets. Both gaskets are the same, so one can "look" wrong as in upside down, but front is front
Can I take one head off and not the other? Can I reuse the bolts? Can I reuse the gasket? I don't see a tab sticking out either the front or the back. These head gaskets Jasper used don't have the tab like my old 302 I replaced did. Is there any other reason water could/should still be in those two ports? I have the lower water pump hose off and I loosened the belt and spun the water pump.
Went out and looked with big flashlight. Square tabs are in the front on both sides of the motor. Head gaskets appear to be installed correctly. Could it be a blockage on the timing chain cover?
OR should I put this all back together? It just bothers me that the passenger side drained and the drivers did not and I have been having overheating issues.
I'd check that rear passage in the intake. Make sure nobody closed it up with RTV or epoxy because it had a crack in it somewhere. The intake and radiator are the only two things you said were common between the two engines, so one of them has to be stopped up not allowing flow.
I think you have a coolant circulation problem caused by an air pocket or an obstruction. I suggested the burping to eliminate an air pocket as cause for poor flow and capacity and it doesn't cost any money or parts. If it overheats after burping then you take the thermostat out and burp it again. Look in the radiator for water flow. If there is low or no flow you need to find the cause. A rear water crossover delete is very common on sbf aftermarket intakes and is not the cause of your problem. Some things to check, does the water pump have a steel plate between it and the front cover? Some parts store pumps don't include the plate. I went and looked at a 79 f-150 in my back yard it has one. Is the pump and the front cover from the same vehicle or something picked out of the pile? There are several variations and not all play well together. Ck for gasket blockage at front cover to block. Take the radiator out and run a garden hose in the top hose inlet with the cap on. See how the flow is coming out the bottom. Remember the cooling system takes water from the lower radiator to the pump into the left bank and the right bank. Through the block up to the back of the head on each side and forward to the front into the intake past the thermostat and back to the radiator. I try to diagnose things in the order of easiest and cheapest first before tearing things down to throw parts at them. Your results may vary!! good luck
Check timing, making sure you have the light hooked to number one, (other side from SBC) Look for a vacuum leak in/on the Edelbrock manifold. Lean=hot..
Thermostats either have a "jiggle valve" for this purpose or, a sized opening if held up to the light. Ford did have a TSB for a while, they suggested prying open the thermostat and jamming a piece of hard candy in it to prop it open temporarily. This keeps thermostat open to allow for a complete fill, then it dissolves. I like that better than drilling holes, which will screw up the temp rating.
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