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1G The Engine Shop From HELL :@

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thejollyrancher

10+ Year Contributor
307
13
Mar 31, 2012
calgary, AB_Canada
This has been one hell of a build, and I think Ive had enough of this crap. I bought a resurfaced head from a user on here and upon getting realized that it was pretty botched. So I took it to a machine shop that found the seats to be just as bad. No big deal right? I test out some new valves after some lapping and have 3 or 4 valves leaking pretty bad so I decide to go back to the machine shop, they quote me 350 to get the valves mated to the seats properly.

A week later I call in and the owner says, and I quote, "oh youre sh*tty a** head, *sigh* ya gimme a couple hours". This upset me quite a bit. I show up that evening, cough up the 350, and go home to test the valves. No cams, I shoot some soapy water in back of the valves, and crank by hand. The whole thing is frothing like a rabid wolf in a chicken coup. 13 LEAKING VALVES! They didn't just f*** up, they went above and beyond! The response I get when I tell them this is "We vacuum test every head before it leaves, and if it passes 18 psi vacuum then were done.". They refuse to believe it doesn't seat. I have videos showing the frothing of the valves and the OBVIOUS leaking, but I keep getting the same "if it passes vacuum testing then its seating". Its not. Its very obviously not. Why the hell else would it be bubbling so much?! :banghead:

Ive had it with this. We have a great platform and a fantastic following, it just feels like when it comes to the modified car scene, people loose their decency.

Any advice on how to proceed? I can obviously see it leaking air both ways, on the up and down travel of the piston it either spits our bubbles or sucks them in. How in the world could it pass vacuum testing? Am I missing something, or are these people as dense as I think?
 
First off that is a poor way to test the valves. You are now going to have rust on the valves, seats, and cylinder walls.

They may have just cut the valves and seats without lapping them. Take the head off, clean everything with wd40 to try to stop rust, and hand lap the valves in.
 
I also did a leakdown test and got 40% - 60%. I shot it with soap to grab a video and bring it in to them, showing the bubbling. At this point I dont want to touch it, as I was told it would seat as is.
 
Hey, I know this is pretty frustrating, and I've had my fair share of issues with my own build, but getting bent out of shape never solved anything.

What did they do for the $350 was it a lapping job or a 3 angle job? I was charged $295 for Cutting valve seats at 3 angles and valves ground to match, hot tank and plug replacement. Most of the time machinists have (depending on the size of the shop) about 20 different projects going on so yours is likely not his only priority. And most have trucker-mouths, too.

You have a machine shop that sounds like they stand behind their product. So my advice would be to take it in to them and show him in person how it's not seating.
 
Hey, I know this is pretty frustrating, and I've had my fair share of issues with my own build, but getting bent out of shape never solved anything.

What did they do for the $350 was it a lapping job or a 3 angle job? I was charged $295 for Cutting valve seats at 3 angles and valves ground to match, hot tank and plug replacement. Most of the time machinists have (depending on the size of the shop) about 20 different projects going on so yours is likely not his only priority. And most have trucker-mouths, too.

You have a machine shop that sounds like they stand behind their product. So my advice would be to take it in to them and show him in person how it's not seating.

Apparently Its a 3 angle valvejob and ground to seat. Machine work is very expensive here though. They said they vacuum tested it to 18psi and it seated. I just dont see how I could explain to them its not seating if it is actually passing vacuum testing. Assuming theyre not B.S.ing me, would it be possible for the head to pass vacuum test and have it leak on the block?
 
Have them vacuum test it in front of you. It's possible they may have missed that step as it sounds like they rushed the final stages of this one by the quote "gimme a couple hours". You paid good money for that work have them prove it to YOU not the other way around.

And don't go be a d*** about it, just go in with the attitude, hey, things happen and this one might've got missed in the line of work. You're just exploring all your options.

:cool:
 
Have them vacuum test it in front of you. It's possible they may have missed that step as it sounds like they rushed the final stages of this one by the quote "gimme a couple hours". You paid good money for that work have them prove it to YOU not the other way around.

And don't go be a d*** about it, just go in with the attitude, hey, things happen and this one might've got missed in the line of work. You're just exploring all your options.

:cool:

Youre exactly right. If the vacuum test holds up to 20 psi im going to be floored though. Is 20 psi enough to know that its seating? Im not quite sure how a vacuum test works but isiit possible that a vacuum test checks out but the valves are still not seating?
 
When testing vacuum on valves you usually have to be a little rough with them. When on a machine you give them a little tap or two. You can even go so far as pushing down on the valve while pulling said vacuum. You have to realize while getting a seal you need the valve springs installed. If you already have them installed you may want to run the engine. The valves really only seat fully after they have had the chance to get up to operating temperature and essentially smack against the seat.

When grinding valves and cutting seats you don't get an instant perfect seal. You can get a pretty decent one but the valves still need to I guess you could say "form" to the seats.

Hope this helps.
 
When testing vacuum on valves you usually have to be a little rough with them. When on a machine you give them a little tap or two. You can even go so far as pushing down on the valve while pulling said vacuum. You have to realize while getting a seal you need the valve springs installed. If you already have them installed you may want to run the engine. The valves really only seat fully after they have had the chance to get up to operating temperature and essentially smack against the seat.

When grinding valves and cutting seats you don't get an instant perfect seal. You can get a pretty decent one but the valves still need to I guess you could say "form" to the seats.

Hope this helps.

That's a good point. I hope that's the issue. Only problem with that is its apparent I had a better seat before I sent the head in. I only had a couple valves leaking, now its almost all of them. But if the vacuum test goes well I think Ill have no choice but to run it and see how it goes.
 
You can go ahead and lap all of the valves to seal while the head is off but in reality they'll fully seat within the first few seconds of the engine running. Usually a machinist will lap the valves after cutting the seats if he's worried about them sealing or if he wants to see where they're sealing/seating. I use a dry erase marker to look at the seating line.

Hope this helps.
 
You can go ahead and lap all of the valves to seal while the head is off but in reality they'll fully seat within the first few seconds of the engine running. Usually a machinist will lap the valves after cutting the seats if he's worried about them sealing or if he wants to see where they're sealing/seating. I use a dry erase marker to look at the seating line.

Hope this helps.

Sweet, Im feeling a bit better about this, hopfully its just that the valves need a lapping. Ill ask the machine shop if they have :thumb:
 
First its not PSI that the valves are tested at it is inches of vacuum.

Next 18 inches is way to low, unless on really rough stone ground seats that have to be beat in.

I look for a min of 25 inches with out springs installed, and 27-29 with the springs installed.
 
First its not PSI that the valves are tested at it is inches of vacuum.

Next 18 inches is way to low, unless on really rough stone ground seats that have to be beat in.

I look for a min of 25 inches with out springs installed, and 27-29 with the springs installed.

I was there today and I got a hold of the owners son who actually worked on my head. He was a lot nicer. He vacuum tested it in front of me and it held 20 inHg. He offered to redo it and vacuum test it again anyways. He urged that after testing I should just install the head without testing it on my block and run it assuring me that it would run.

Ill tell him to test it to 29 inches in front of me when I go pick it up tomorrow. Thanks
 
The owner was a real piece of work but his son owned up and redid it. He did a vacuum test to 25 inches without springs and it looked good. I have it out together and going to slap it on next weekend
 
The valves really only seat fully after they have had the chance to get up to operating temperature and essentially smack against the seat.

When grinding valves and cutting seats you don't get an instant perfect seal. You can get a pretty decent one but the valves still need to I guess you could say "form" to the seats.

Hope this helps.

This is not true. Bad tech advice. A properly machined and lapped valve will seal 100% before the engine is fired up. I do a vacuum test to 20 in/Hg before a head goes onto the engine and then a leakdown test after the engine is completely assembled. Anything less than 100% seal with vacuum is unacceptable. Anything less than 4-6% leakdown test is unacceptable. There is no need for the valve to "smack" the seat to "form" in place.
 
This is not true. Bad tech advice. A properly machined and lapped valve will seal 100% before the engine is fired up. I do a vacuum test to 20 in/Hg before a head goes onto the engine and then a leakdown test after the engine is completely assembled. Anything less than 100% seal with vacuum is unacceptable. Anything less than 4-6% leakdown test is unacceptable. There is no need for the valve to "smack" the seat to "form" in place.

Oh! I'm sure if you're going to take the time to lap every single valve individually this would not be the case. There is nothing wrong with not lapping every single valve however. You may disagree but that simply shows individual preference. If one is lapping every valve it would indeed make sense there is no "need" for them to mate to the seat or vice-versa. I guess it would depend how nice of machine setups you are running/have as well. Either way there are lots of variations and if you don't know what you're doing you're not going to get a decent seal.
 
Nope. Still wrong. If it doesn't seal on the bench it's only going to get worse on the car. Bad contact area between the seat and valve results in accelerated wear and burned valves. It has nothing to do with lapping or personal preference.
 
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This has been one hell of a build, and I think Ive had enough of this crap. I bought a resurfaced head from a user on here and upon getting realized that it was pretty botched. So I took it to a machine shop that found the seats to be just as bad. No big deal right? I test out some new valves after some lapping and have 3 or 4 valves leaking pretty bad so I decide to go back to the machine shop, they quote me 350 to get the valves mated to the seats properly.

A week later I call in and the owner says, and I quote, "oh youre sh*tty a** head, *sigh* ya gimme a couple hours". This upset me quite a bit. I show up that evening, cough up the 350, and go home to test the valves. No cams, I shoot some soapy water in back of the valves, and crank by hand. The whole thing is frothing like a rabid wolf in a chicken coup. 13 LEAKING VALVES! They didn't just f*** up, they went above and beyond! The response I get when I tell them this is "We vacuum test every head before it leaves, and if it passes 18 psi vacuum then were done.". They refuse to believe it doesn't seat. I have videos showing the frothing of the valves and the OBVIOUS leaking, but I keep getting the same "if it passes vacuum testing then its seating". Its not. Its very obviously not. Why the hell else would it be bubbling so much?! :banghead:

Ive had it with this. We have a great platform and a fantastic following, it just feels like when it comes to the modified car scene, people loose their decency.

Any advice on how to proceed? I can obviously see it leaking air both ways, on the up and down travel of the piston it either spits our bubbles or sucks them in. How in the world could it pass vacuum testing? Am I missing something, or are these people as dense as I think?


I have found that otherwise completely competent local machinists with good reputations just can NOT handle any aspect of the 4g63. Do i understand? NO.
Must go to well known builders and ship it out man.

At first glance i thought this was going to be a thread about SIM............yea....................ummmmmm take my advice, stay away. I have a thread from last year before back surgery that documented the issues. Took 3 tries to get it right. Engine hasn't been assembled but 3rd time i think they got it right. Costly $1500 mistake. I would say JAM or theres a guy out of florida on here who is very very good. I can't remember his username for the life of me.
Lol EDIT: I didn't read the comments: Bogus is right here.
Hey bogus: I would have definitely sent my head to you last year but you were dealing with a flooded shop and all that shit. I'll contact you next time i need some work.
 
This is not true. Bad tech advice. A properly machined and lapped valve will seal 100% before the engine is fired up. I do a vacuum test to 20 in/Hg before a head goes onto the engine and then a leakdown test after the engine is completely assembled. Anything less than 100% seal with vacuum is unacceptable. Anything less than 4-6% leakdown test is unacceptable. There is no need for the valve to "smack" the seat to "form" in place.

Thhis is the EXACT same thing i was told when i got my head back from SIM the 2nd time. I called bullshit as well.
 
Nope. Still wrong. If it doesn't seal on the bench it's only going to get worse on the car. Bad contact area between the seat and valve results in accelerated wear and burned valves. It has nothing to do with lapping or personal preference.

Haha, well regardless I've never had an issue getting a 20+ vacuum or seal. Have a good one, God bless.
 

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I wen't to a machine shop that was local around here when I first got into DSM's. They raped me on pricing and added things that were not needed for a stock rebuild. The head machinist also had a horrible attitude because it wasn't his preference of engine. I would never go back to a machine like the one I went too or would I go to one like you went too that said you had a "shittty head".

You are there to pay for a quality service and result, not negative opinions and half assed work. If they dislike working on the platform then don't do the work. This is a terrible business practice that leaves a negative impact on customer/shop relatonships. I had a horrible experience with the shop I first went too and have nothing but bad things to say to anyone who brings them up. If you continue to get crappy service from this shop or even that single experience would be enough for me to find another shop next time around.

The current shop I deal with has done work with me for the last 8 yrs and I have never had a single issue. Who ever suggested that you have the head tested in front of you was the correct answer. The shop I deal with will check a head for me with a machinist straight edge and vacuum test a head in front of me if he isn't busy. Sometimes he doesn't even charge me because I have done so much work with him.

I hope you get a good seal on your head and they should have lapped the valves in for you. Keep searching. You will find a shop that conducts themselves like professionals.
 
Must be a lot of bad machine shops out there. When I did my head took it to my local guys he has been building dirt track race motors for 30 years he charged me $117 to deck, grind valves, new seals, clean it, ect all the normal stuff he also did my buddies head for same price we have had zero issues. Sometimes the old boys are the ones to go to. Will be doing my botum end this winter and I feel he is the one to do it I asked him bout all I want some and he said can do it. I'm going to guess though sense he has been building race motors his hole life he knows what's ok and what's not.
 
I ran into problems with a machine shop not being able to cut the valves properly. First the seat was way too wide, second they didn't true the cutter with the valve guide. I got royally pissed and took the head back(didn't pay a cent), ended up buying neway valve cutters for small engines and machined down the supplied valve guide pilot to work in the 4g63 valve guide. Then cut the valves myself and was able to add a 4th angle for better flow. I lightly hand lapped the valves and tested for a proper seat with a light amount of Prussian Blue. I have since cut the valves on 3 heads and have never had problems. The first one I did has been apart since, had around 30,000 miles and no burnt valves. Cutters were like 250$ like 8 years ago LOL. The hardened seats in these turbo heads seem to hold up very well and from my experience if your machine shop is so so your better off not messing with the seats.

FYI a "3 angle valve job" is essential for any automotive engine built since probly the 70's. I wouldn't run a single angle on my lawn mower. Don't pay more for a "3 angle" or your getting ripped off its standard practice unless your shop deals with brigs and straton LOL. 3 angle(standard), 5 angle(performance), complete radius(racing). The whole point is to create a radius with the angles for better flow with one being the seat. Usually the intake is never taken past 5 angles(radius) to create a little turbulence to mix the air/fuel and the exhaust has the radius for pure flow.
 
Thhis is the EXACT same thing i was told when i got my head back from SIM the 2nd time. I called bullshit as well.
I also back this up as well. After I got my head from SIM, they all leaked with oil poured in the combustion bowl. I cut my losses with them right there. If they can't cut valves, I don't want to think about what else they can't do. There was already a number of other things I wasn't happy with as well. I took it to a local old school hot rod guy who does sleeving of the VQs and Honda blocks. I asked him about that whole slamming the valves to make the seal and he looked at me like I was crazy. When I got it back later, I asked him how did they look and he said they weren't cut at all. I redid the oil test when I got home and other than a one or two of the valves seeping a tiny bit, the rest were holding the oil solid. I wrote that as a pass in my book.
 
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