Cylinder Head Replacement!?

[Trevor-DOHC]

Hi Everyone, So I has a question pertaining to a problem that occurred last Year June, I snapped my timing belt (91TSIAWD) originally I figured I would just PM some of the moderators and what not instead of Threading just in case this was a repeat, however one of them told me I should make a thread! So.....

So my question: I have snapped the timing belt I was thinking since others have told me just get the Head replaced you will be fine.... Will I? Really be?
If I just simply find a used Head for a quick fix with Decent KM & buy a New gasket along with tensioner because I broke mine in the process of removing it not thinking I need a water pump but optional I guess right? Would this be Fine or is there other things I am over looking for problems that might have occurred? I apologize if these seams like a question easy answered. Hope it was Ok to post this! you guys are all the best for solutions always!!

 

[Bud92gsx]

Do timing belt, water pump, tensioner, and new head..Call it a day and have your car back on the road...

You could fix the head you have...But if you want a quick fix..Replace the head..

 

[DSMDEMON93]

A simple phrase I had learned in this community saved me thousands of dollars in heartache...."If it ain't broke, don't fix it." Either way, save the hassle of removing the cams, valves, springs, etc..and buy just another complete head. Change the headgasket as well, and whatever else is broken.

 

[luv2rallye]

Call a machine shop and ask typical price and time to overhaul your head with 4-6 bent valves due to timing belt break. You'll leave the cams, valves, springs, etc on when you bring it to them. They usually have less than a week turn around time. If you buy used head, unless it's been overhauled, you typically get someone else's problem, the wrong one, or one that won't last a year.

 

[cord]

i paid 150$ for all new valve guides and valve seat grinds. i took them the head striped and somewhat clean. did the rest myself.also had to buy new valves. seals came with top end gasket kit.another1oo i think i spent around 500 with new tensioner and belt payed 200 for the verry clean car so its ben well worth it.

 

[teampruven01]

i just bought a head from J&C on ebay, 300 bucks for a completely remanned head, free shipping and they pay for your core to go back too. comes with cams and all. ready to bolt in. just need to get cam seals.

 

[cord]

thats a good deal! i wonder if they have options for better valves im buiding another motor now, 91 eclipse.

 

[TofastForU_99]

Feel free to shoot me a pm with any questions about a cylinder head build. We have a lot of our cylunder heads out and about. We also have a sale with free shipping this month.

 

[Diamond Star Werks]

So my question: I have snapped the timing belt I was thinking since others have told me just get the Head replaced you will be fine.... Will I? Really be?
If I just simply find a used Head for a quick fix with Decent KM & buy a New gasket along with tensioner because I broke mine in the process of removing it not thinking I need a water pump but optional I guess right? Would this be Fine or is there other things I am over looking for problems that might have occurred? I apologize if these seams like a question easy answered. Hope it was Ok to post this! you guys are all the best for solutions always!!

The most reliable solution would be to redo your head. If you take the head to them they should be able to look it over right quick and give you a good estimate on approximately what it will cost. They generally have standard prices for pressure checks, resurfacing, and valve jobs. When i rebuilt my engine I replaced all valves and did a valve job 175$ and resurface 45$ not including valves. Valves were about 11 dollars apiece for me i think because I bought good ones but cheaper ones are available. I had all machine work done to block and head done for 449$ including hot tanking everything, cleaning all surfaces, .40 cylinder bore, remove and install new pistons, polish crank, and all head work. They installed the valves i just had to put the cams on. Rebuilding is the most reliable option to keep you from having another problem. I tried to go the buy another head and slap it on route. Paid 150 for the head but when I had it checked out ending price of using it was about the same as rebuilding mine. But somewhere one of my cam caps disappeared. So had to rebuild the 150$ head. Do it right and rebuild your head. It's the best option.

 

[99gst_racer]

is there other things I am over looking for problems that might have occurred?

You'll also need to address the pistons. If they smacked the valves hard enough, it possible that you could have cracked or broken top lands. in which case, the pistons would need to be replaced. If the top lands are OK, you'll still need to address the dents in the piston decks. Those dents have sharp edges and a sharp edge is a perfect catalyst for a hot spot. A hot spot is exactly what it sounds like. It's a area of a piston dome that glows hotter than the rest of the piston. The hot spot area can and usually will promote pre-ignition (detonation), which can eventually destroy the piston and/or rod bearing among other things. Many people even go as far as to smooth out the edges of valve reliefs on brand new pistons to reduce the chances of them becoming hot spots. In most cases when the valves contact the pistons on these engines, it leaves a mark that is decently wide and not very deep. These are easy to file smooth and reduce edges and that's definitely something you'll have to do. And for doing that work, I'd recommend one of these alumina zirconia pieces. They are absolutely perfect for deburring the dings in pistons. These are found at any hardware store for around $1-2.

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[Diamond Star Werks]

^^^^^^^yes do this also. The mod knows what he is talking about. I didn't have to worry about that so much as I bought everything brand new and bought special coated pistons but as your not you will definitely need to address the areas where the the valves hit.

 

[Calan]

You mentioned that this happened last June... has the motor been disassembled (head removed) and sitting all this time, or is it all still together?

After sitting that long, and depending on climate, etc... it wouldn't hurt to pull the pan and inspect the cylinder walls for corrosion (although it's probably not an issue). And while your at it, check the pan for any small pieces of debri that might have been caused when the belt/valves let go.

 

[Trevor-DOHC]

Yes the Head has been removed, it has actually been sitting since October last year so just over a year. I did cover it the best I could, Hoping no rust would come.... Im just needing my car/a car ASAP! Figured getting a used Head and replacing it would be pretty basic & easy, also more affordable than a used clunker that would probably be more un reliable. So what I figured on doing first is checking for rust by taking the Pan off, then if all is ok Shave down the piston heads a lil bit from where contact was made (didn't look bad really) Spray some WD40 around the piston walls, then put the Head back on as well as the other essential components for the install pf course! This should be Fine correct? I just wanna be sure, however I know somethings aren't always a guarantee with cars, I just dont wanna be out 4-5 hundred dollars. Yes, I only made one phone call to a machine shop asked for about a 4G63 Cyl Head Overhaul they quoted me like 500 at least, Not the only shop in town so I guess I might be able to find cheaper by phoning around a lil more?
So It might be better to get a whole Cyl Head Rebuild, im just hoping it will be affordable for me right now!

 

[SpeedTech720]

If you buy a new head make sure you get it from a vender or can inspect it yourself before buying. I've bought one on ebay and another on here that were both "rebuilt fresh from the machine shop". The CarQuest here has a machine shop that is pretty cheap to fix the first one but the cost was still additional to buying & shipping the head. The shop that fixed the second has done many DSM builds so they were relatively cheap as well. Make sure you buy a quality belt set too! You don't want the same thing to happen again.

 

[nastynine]

i would replace everything at once so its less of a hassle in the long run.. you don't want it to happen again.. i would replace the water pump tensioner and if you do end up getting a used head you may want to consider getting it resurfaced and purchasing a name brand head gasket..

 

[Empire1208]

Feel free to shoot me a pm with any questions about a cylinder head build. We have a lot of our cylunder heads out and about. We also have a sale with free shipping this month.

^^^^^^^ i say hit em up ^^^^^^^^

Guaranteed you bent the valves! when you take the head off inspect the pistons as stated. You mights as well change the water pump/timing belt/ as stated too. DO IT RIGHT ONCE and be done with it!! GOODLUCK