If you can position it such that the whole surface of is illuminated with no parts in shadow, then wouldn't that mean you have a reasonably flat surface?
Using a laser to check if a cylinder head is flat - any reason why this wouldn't work? (1 Viewer)
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seems somewhat reasonable but can you guarantee you aren't at a slight angle pointing in toward the far end of the cylinder?
I'd like to see the same laser on a freshly machined head.
ALSO, if you're going table top laser level/flat gauge, maybe just give it one of those glass table top/sand paper flatting jobs to be safe
I'd like to see the same laser on a freshly machined head.
ALSO, if you're going table top laser level/flat gauge, maybe just give it one of those glass table top/sand paper flatting jobs to be safe
- Thread starter
- #4
Hi OSS,
Love seeing your comments on everything 2F/FJ60 related that I look up.
Honored that you commented on my own question.
I'm always suspicious of going to someone and paying them to potentially tell me I need to give them more money for something I can't verify. If I can figure out a way to avoid that I will.
Got quoted $500+ by a machine shop today to refurbish this.
Deck flatness although important, the most important part of a head rebuild Are valve guides. Next most important are to buy NEW valves and cut seats. Last the deck flatness, which is the easy part of a head rebuild.
You can check valve guides by inserting the valve and wiggling it side to side, if there is any play you need new guides. If your head has 100k mi or more it most likely needs guides.
You can check the seats by inserting a valve in the guide and dropping the valve vertically. If it does not bounce straight back up you need the seat cut/ ground.
Keep in mind the guides and seating of valves work together to keep oil out of the chamber and compression tight. Deck flatness is last on the list of importance and the cheapest machining operation of the head
You can check valve guides by inserting the valve and wiggling it side to side, if there is any play you need new guides. If your head has 100k mi or more it most likely needs guides.
You can check the seats by inserting a valve in the guide and dropping the valve vertically. If it does not bounce straight back up you need the seat cut/ ground.
Keep in mind the guides and seating of valves work together to keep oil out of the chamber and compression tight. Deck flatness is last on the list of importance and the cheapest machining operation of the head
My .02 cents.
An inline 6 has a LOT of room to warp a head, especially on a smog motor that runs lean and hot with siamesed exhaust ports. Going cheap here, will guarantee you disappointment at some point, or worry over every blip of the temp gauge if you throw it together without knowing. A long straightedge is mandatory to check for warping. If you don't have access to a machine shop, you'll have to find a way to check it. Having it professionally cleaned and magnafluxed is cheap insurance before you spend money fixing it and buying lots of new parts; after all, you are dealing with at least a 30 year old part, if not closer to 35. The valves can easily be checked with a micrometer for wear on the stems and a visual inspection of the seating surfaces and the margins will tell you where you are on service life. Exhausts tend to erode under the heads and subsequently lose their heads more often than intakes. This is made worse when you are making more power than stock or you are running it wide open because it's a "new" engine, so it "ought" to be able to take it...
Yes, you can go cheap and roll the dice, but how much is your time and those new gaskets worth to you, plus you get to pay twice for all the fluids. Can it be done, yes. Should it be done? Your call. Remember, oil is $5 a quart for the cheap stuff and antifreeze is $9 a gallon for the cheap stuff. At that price, buying it twice will pay for most shops to clean and crack test a head.
An inline 6 has a LOT of room to warp a head, especially on a smog motor that runs lean and hot with siamesed exhaust ports. Going cheap here, will guarantee you disappointment at some point, or worry over every blip of the temp gauge if you throw it together without knowing. A long straightedge is mandatory to check for warping. If you don't have access to a machine shop, you'll have to find a way to check it. Having it professionally cleaned and magnafluxed is cheap insurance before you spend money fixing it and buying lots of new parts; after all, you are dealing with at least a 30 year old part, if not closer to 35. The valves can easily be checked with a micrometer for wear on the stems and a visual inspection of the seating surfaces and the margins will tell you where you are on service life. Exhausts tend to erode under the heads and subsequently lose their heads more often than intakes. This is made worse when you are making more power than stock or you are running it wide open because it's a "new" engine, so it "ought" to be able to take it...
Yes, you can go cheap and roll the dice, but how much is your time and those new gaskets worth to you, plus you get to pay twice for all the fluids. Can it be done, yes. Should it be done? Your call. Remember, oil is $5 a quart for the cheap stuff and antifreeze is $9 a gallon for the cheap stuff. At that price, buying it twice will pay for most shops to clean and crack test a head.
cps432
SILVER Star
Don’t use sandpaper and glass. I tried that and had to stop because the glass was warping just enough to follow the warpage of the cast iron. I used 5/8” tempered shower glass and it still had too much movement. Just go to a machine shop. It’s nice to know how much material was removed and you can’t know that using sandpaper.
If you’re in the middle of Sub Sahara Africa and you have no options then sandpaper would be your best bet, however, if you can get to a machine shop that’s what you should do even if you have to wait or take a trip to the next town.
You would be surprised at how much warp in a head that can be overcome with the compression of the head gasket.
You could buy a .001” indicator and rig up a way to check your flatness, but that money would be better spent on new valves and guides IMO
You could buy a .001” indicator and rig up a way to check your flatness, but that money would be better spent on new valves and guides IMO
dude you already have it off! might as well drop it at the machine shop! take your exhaust manifolds and intake manifold for them to machine while youre at it! Then you can enjoy not having any intake/exhaust leaks and not worry about headgaskets haha
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