Say, if a head is cracked, what would be the signs when you tear down the engine?
Stop in for a cup of coffee
- Thread starter toolmanmike
- Start date
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Oil in with antifreeze(not always) , visible cracks
The machine shop wanted to know if they should pressure test them and since I don't have their history, I'm hesitating. It isn't cheap but then again, doing the work on crecked heads is an even worse deal.
I wrote to the seller and he said the engine looked really nice inside and I guess he would have noticed if water had leaked into the oil, right?
I would have them at least magnafluxed, seems pretty standard over here.
Wouldn't a mag flux be good to find any cracks ?
LOL repeater!
Preassure testing I am not familiar with at all. Would that just check the chambers? I know Mag flux does everything, chambers, ports, guides etc.
But not the internals of the head. I talked to them about that.
Have them sonic checked or magnaflux.
The only way to check that is gonna to be to sonic test then
so what does pressure testing do? I know on aircraft we either mag fluxed, megger checked or x rayed if needed.
Pressure testing isn't commonly done, normally a diesel or industrial thing as opposed to the standard gas engine. Essentially it's like flow testing by bolting the head down to a plate and testing not only the chambers, but the water ports, oil passageways and intake and exhaust ports. Done one by one, time consuming and not cheap. Essentially filling the head passages with pressure and waiting to see if any psi bleeds off. Sonic testing can do it much faster which is why pressure testing isn't done much these days.
I never ran into it, makes sense Diesel engines with high pressures, lot more cars over there with diesels.
Usually it's done on the high mileage OTR rebuilds for semis. The thought process is that if you fill the chamber/passageway to its rated psi and it holds without busting a hole, the head can be reused. The same with the block though normally they just sonic test the block as the highest risk of a blow out due to fatigue is in the head
You have new seals Anders? Prob can get away with the springs tested.
Well not really, we posted at the same time
I never seen your post
So...A magnaflux is all I have ever dun to the heads I have checked for leaks and cracks
Haven't ordered seals. I'm thinking I'll let the machine guy supply them. That way I can be sure they're in there ok. Same with the seats. I may not replace the seats after all. I'll let him decide.
I'm a little confused by the different stem diameters available. Kind of freaking me out. I don't want to get valves that have too much slop in the guide. Or too little.
1964 Plymouth Valiant convertible
Nice car!
Nice car!
Wait, not seals. I was thinking of guides.
As far as seals go, I'm leaning towards machining for positive seals. That will need to be done after I decide on springs, though, which is dependent on cam choice.
ScampMike
Despicable Damn Yankee
whew - I shoulda stayed the frig home.. of course, I feel like that everyday so...
Yup, Thats how it is here. Feast or famine. I have a small shop at my house. I usually try to do a couple a jobs a week. All easy stuff Brakes, Axels, Pm's etc. I dont really need the money, but it helps , parts for the Mopars. Sometimes Ill go two weeks without a call. This past week I had 8 calls and 8 jobs in the last two weeks. Yup, Feast or famine
Man that's to busy!
Hey Ray
Whats UP? Just about ready to hit the shop.
Scrapping mastic off kitchen floor, is a *****, just about dun , about to get outside and stretch a bit (No @krazykuda I don't have a bit in my mouth) 
Have a good one every one 
Have a good one every one -
