So I was driving down the road for about an hour and a half in about 95 degree weather in my 74 maverick with a 250 I6. Suddenly I started to loose power and couldn't get over 60. I was trying to make it to the next rest stop and maybe let it cool off but before I got there it suddenly started knocking. And not a "did you hear that? sounded kinda weird" knocking, more like a "Oh my god! A bird flew into my fan belt and my engine is going to explode!" knocking. So I pulled over, I was way over heated, the coolant was boiling out and no bird to be seen. There wasn't any smoke even the next day after I tried starting it up again. So I can only assume I overheated my engine and caused a more sever problem. Ive asked around and the general consensus is a blown head gasket. I would like to know what you guys think and what I should be on the look out for. If you think its a head gasket great, if you think its something harder to fix.. well dang.. Thanks for your help in advanced.
You more than likely have a blown head gasket by now, if thats not what caused your overheating in the first place. The knocking was probably detonation starting. It never pays to keep running the engine when it gets to a certain temp. It's always best to just pull over and let it cool down, then try moving later, it may be time consuming, but you could run the engine for 5 mins a time before it would heat up again assuming a full cool down. It may just take you 3 hours to get home, if you cant afford a tow. Was the exhaust manifold glowing?
I didnt see anything glowing, and I spent a long time looking in to see if anything was noticeably leaking or out of place. But everything looked normal. Except the loud knocking sound and huge vibrations comming from the engine every time I tried to start it.
So I took my head apart today in order to change my head gasket and I just want to make sure its the head gasket that is causing the knocking in my engine. What else should I be looking for while I have it apart? I am no expert but everything seems alright, nothing obvious at least. Also I want to mention that the 2nd cylinder was up at the top with the 1st cylinder and I could easily push it down until it was at the same height as cylinder 5. Is this a bad thing? if so what does it mean? if not... what does it mean? Any advise would be much appreciated, thank you much.
Sounds like you may have banged out a connecting rod bearing.Since you have the head off, midas well pull the pan and do a look see at the bottom end...
When you say push down, did you push down by hand an no other pistons moved? Sounds like you broke a connecting rod. Time for rebuild or short block if so. Good Luck an keep us posted.
I moved it down with the weight of my index finger, none of the other pistons moved. Any ideas on where to get bigger and better prats, aside from fordsix.com and cliffordperformance.com?
Yep, broke a rod. That's bad. Time to rebuild it or replace it with another motor. I'd bet the cylinder wall on that cylinder is screwed up. Probably cheaper to just find another motor.
Hey, I found the problem! It was a connection rod bearing, and a connection rod... and now there is a little tiny hole in the bottom of my cylinder(pictures attached) So how big of a problem is this? New engine time? Or is this manageable? I am assuming new engine, but eh. Thank you all for your help, I couldn't have found the problem with out it.
If that is far enough down not to be in an area where the rings would go past it, you may get away with chamfering the edge of the break, checking rod journal on the crank shaft to be sure it's alright, and just replacing the piston and rod. If you can't do that, then at the very least you will need another short block.
With your next engine have the 11/32" ARP rod bolts intalled so they don't stretch and break like that again. I wouldn't use the block. That part of the cylinder supports the piston when it is at the bottom of it's stroke. Blocks are cheap when you compare it to what could go wrong again.
