NCchris Posted March 18, 2007 Share Posted March 18, 2007 Anybody have a clue what could have caused this? Can it be fixed? Just bought this head over the internet. Am I sol? Thanks for any help. chris Quote Link to comment Share on other sites More sharing options...
Administrators BRAAP Posted March 18, 2007 Administrators Share Posted March 18, 2007 It is savable… You are NOT SOL. That can be welded up, and then using a head gasket as your template, just redrill the hole to the same size as the head gasket,, also run a drill bit down the head bolt hole to clear it out for the head bolt, then have the head resurfaced and it will be good to go. If the head is currently warped, the cam, valves, springs, rocker pivots, etc will all need to be removed and the top surfaced as well. Any automotive machine shop can tell you if it is warped. Any shop that can weld aluminum with even minimal skill can weld up the corroded/eroded port. It appears that someone took one of those scotch brite buffer discs to the deck surface, so not mater what, especially in a boosted application, that head needs to be resurfaced. Don’t get me started on mechanics or garage engine builders using buffer wheels for gasket prep… I see that port corroded/eroded like that all the time on L-series heads, but I have never seen one that bad. Good luck, Paul Ruschman Rusch Motorsports Quote Link to comment Share on other sites More sharing options...
NCchris Posted March 18, 2007 Author Share Posted March 18, 2007 Thanks for your speedy comments. I thought it could be salvaged, but wanted to ask the experts. All the other coolant passages are not eroded at all! Speaking of engine building do's and don'ts. The bolts holding the cam towers were nearly bottomed out and weren't even close to being down. Upon removal, I found the holes full of glass bead media! I'm building a turbomotor for my 260 with a turbo short block and flattop pistons so didn't want to surface it much. Thanks chris Quote Link to comment Share on other sites More sharing options...
Thanh Posted March 18, 2007 Share Posted March 18, 2007 Thanks for your speedy comments. I thought it could be salvaged, but wanted to ask the experts. All the other coolant passages are not eroded at all! Speaking of engine building do's and don'ts. The bolts holding the cam towers were nearly bottomed out and weren't even close to being down. Upon removal, I found the holes full of glass bead media! I'm building a turbomotor for my 260 with a turbo short block and flattop pistons so didn't want to surface it much. Thanks chris Had the same thing happen to me man. I bought a nice P90 head on ebay. EVERYTHING was in great condition. Then I taken a look closer with my cousin and he sees it all. The water jacket was rotted straight through. The buyer was generous enough to stop at my house and pick it up. He refunded me later. Quote Link to comment Share on other sites More sharing options...
Administrators BRAAP Posted March 18, 2007 Administrators Share Posted March 18, 2007 NCchris, Just curious, is this head supposed to be a freshly remanufactured head ,i.e. machined and assembled ready to run, and has not been on an engine yet, or is this a head that was removed from a running engine? I’ll address the bead blast media issue in a little bit… Quote Link to comment Share on other sites More sharing options...
NCchris Posted March 18, 2007 Author Share Posted March 18, 2007 NCchris,Just curious, is this head supposed to be a freshly remanufactured head ? No, this was not advertised ready to run. In the seller's defense, he only represented this as a used P90 head in good condition, no warranty implied. I did not ask about any specific problems, just general condition. My bad. If it weren't for this and two broken studs, this head would be pristine. chris Quote Link to comment Share on other sites More sharing options...
Challenger Posted March 19, 2007 Share Posted March 19, 2007 Don’t get me started on mechanics or garage engine builders using buffer wheels for gasket prep… Yeah I guess alot of mechanics think that the scotchbright wheels dont take off material, the guy that "fixed" my head did the same and we had to get it resurfaced. Quote Link to comment Share on other sites More sharing options...
Administrators BRAAP Posted March 19, 2007 Administrators Share Posted March 19, 2007 Being as your head wasn’t cleaned thoroughly previously, i.e. the presence of media blast, (don’t use the machine shop that did this EVER), that head needs to be completely and totally stripped down to just the bare casting and thoroughly cleaned, (you can leave the valve guides and valve seats in place), i.e. every removable part that can be removed with ordinary hand tools, including the rocker pivot bushings needs to be removed. If the head has not been ran, i.e. not oily, then skip to #2. 1) If the head has been ran, i.e. oily, after disassembly take it down to any local automotive machine shop and have them “jet wash†the head. When you get it back , go on to step #2. 2) Now with a fresh water source and an air nozzle, (hose bib on the side of your house/garage/shop is just perfect), spend at least 30 minutes rinsing, blowing out, rinsing, blowing out, rerinsing, more blowing out, and keep doing that for that at least 30mintues. While rinsing, turn and place the head in every conceivable position and angle to get the water into every crevice to help release the media blast. The idea is to release ALL of the bead blast media from every nook and cranny within the head including the water ports, bolt holes, etc. Do NOT use solvent! Solvent will just ball up the media. Water and compressed air are the best agents for releasing the media blast. You will also want to due the same with cam shaft as it has in internal oil passage. Don’t forget the cam towers. Speaking of oil passages, the oil passage in the head itself needs a thorough cleaning as well. Best way to do this is to remove the pressed on galley plugs, (drill out the plug, but don’t drill it oversize unless you plan to install larger NPT plugs), and perform the whole water-air clenaing procedure there, don’t forget the 2 oil feed holes on the deck surface, one in the middle of the head passenger side, and the front of the head. Oh, and the cam tower feeders. For plugging those galleys when you are finished, you can purchase those OE press plugs, but we always drill and tap them for NPT plugs and for added safety, we use our die grinder with the long bit to ensure that the oil passage that goes the deck surface at the front of the head, receives unobstructed flow as the NPT plug gets right close to blocking that port. Also, the front galley plug has to be flush with the cast surface, i.e. not protruding out, in order to clear the slack side of the timing chain as it runs across that plug. 3) Now is also good time to chase “all†the treads in the head. 6 x 1.0 mm for the valve cover and timing chain inspection cover. 8 x 1.25 mm for the cam tower bolts, fuel pump block off, fuel rail mount, cyl head lifting tab, thermostat housing, all the exhaust mount holes and carb intake mount holes. 10 x 1.25 mm for the four EFI manifold holes. And 14 x 1.25 mm for the spark plug threads. When you’re done with that, compressed air, then one more thorough rinsing and you’re ready for assembly. Don’t forget to “immediately†spray the valve guides and valve seats with some sort of water displacer/rust inhibitor such as WD/40 after the final rinsing and blow down to keep those parts from rusting. Proper head assembly details are also just as involved, being as I’ve already jacked this thread to far off topic, I’ll just leave it at that… I’ve covered some of those assembly details in other posts… Hope this helps, Paul Ruschman Rusch Motorsports Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.