alextangent Posted July 17, 2006 Share Posted July 17, 2006 I need to remove the exhaust manifold as one of the gaskets is leaking. Can't get out 4 of the 6 bolts as they're too badly corroded; tried everything ☹️. They're the two in the centre and the top ones of the left & right. What are the alternatives? Helicoiling? Does the head need to come off for that? What kind of cost am I looking at? It's leaded, so should I take the opportunity to upgrade to unleaded? Again, cost? It's a 1700 supersprint xflow 1993, looks like a standard caterham engine. Replies appreciated. Link to comment Share on other sites More sharing options...
DohNut Posted July 18, 2006 Share Posted July 18, 2006 I know you said everything, but I would first by a socket Hex key and a breaker bar and have a go after a couple days soaking in lubricant. Something will move - it will either come out or break If it breaks you will have to drill out the stud and re-tap, That is what JWhiting did to mine several years ago. There is room i think to drill out the studs in situ, but I would not trust myself to get it drilled straight The only downside is that if you break the bolt at home you have an undrivable car but I would suggest you would get a better job taking the head off and getting it to a machine/engine shop One you have the head in the machine shop there is no better time to get other things done. Nick Link to comment Share on other sites More sharing options...
Molecular--Bob Posted July 18, 2006 Share Posted July 18, 2006 It is possible to break the stud housing for the central ports, so make sure you have allowed the release agent to do its job before the brute force is applied. I need to look into getting an unleaded head for my 1990 Supersprint, does anyone Know what the nearest off the shelf equivalent would be from Burtons or Vulcan. Link to comment Share on other sites More sharing options...
DohNut Posted July 18, 2006 Share Posted July 18, 2006 That reminds me The top outside bolts are accessible from the back for WD40 etc. Nick Link to comment Share on other sites More sharing options...
alextangent Posted July 18, 2006 Author Share Posted July 18, 2006 I've tried the soaking in Wd40 and the breaker bar approach... The problem is that the corrosion has eaten away the inside of the hex on the bolts, and there's not enough metal left to take the force. ☹️ I think I'll take it to the garage I get my tintop serviced at; they're pretty trustworthy and the head mecahnic knows quite a bit about xflows. I wonder if an air tool might release it; they use a hammmering action? If the fallback is a new head, who would you recommend for an unleaded 1700? Burton? Vulcan? Thanks Link to comment Share on other sites More sharing options...
Normans_Ghost Posted July 18, 2006 Share Posted July 18, 2006 Hex socket and breaker bar. Also get a largish drift and a medium sized lump (club) hammer and hit the end of the bolt fairly sharply two or three times. Not hard enough to damage the head, just hard enough to break the rust between bolt and head. Soak in penetrating fluid such as Plus Gas. Norman Verona, 1989 BDR 220bhp, Reg: B16BDR, Mem No 2166, the full story here You and your seven to The French Blatting Company Limited Link to comment Share on other sites More sharing options...
DohNut Posted July 18, 2006 Share Posted July 18, 2006 If you think that it has really reached a stage where you think that no-one will ever be able to unscrew the bolts then you can grind them off. once they are off you can take off the head to get the bolts drilled out. This should not be reason to trash a head. I have a vulcan head and would take the removed head there to ask for a quote to remove the bolts and fit unleaded inserts - he may take the head in exchange, you may decide to have larger valves etc. - I am not sure what he has on the shelf. Nick Nick Link to comment Share on other sites More sharing options...
Area Representative Golf Juliet Tango Posted July 18, 2006 Area Representative Share Posted July 18, 2006 Use something better than WD40 try PlusGas first and someone will soon be along with even better stuff. GJT Crossflow 524 my secret Link to comment Share on other sites More sharing options...
Martyn Heesom Posted July 18, 2006 Share Posted July 18, 2006 If you cut the heads off the bolts (with a grinder or a hacksaw) and get the manifold off you may be able to remove what's left of the bolts with a stud extractor or a mole wrench, without having to remove the head from the engine. Link to comment Share on other sites More sharing options...
alextangent Posted July 18, 2006 Author Share Posted July 18, 2006 OK, I'm going to get some PlusGas, soak, bang with a punch & hammer, and use breaker bar until the b*****s shift or bust. If they bust, angle grind off the remainder, try molegrips etc, or get drilled out. Sounds like a plan! 😬 Still wondering; how much is an unleaded head? Link to comment Share on other sites More sharing options...
JampJ Posted July 18, 2006 Share Posted July 18, 2006 The best way to remove them is by applying heat to the bolts, directly, or by welding a nut onto them so you have something to grip. The problem is the small amount of room you have to get at them. If you cut the head off some Cap Headed Allen bolts and weld them on top of the existing bolts, the heat should allow you to remove them using a T wrench. I'd replace them with stainless Cap heads and use a smear of copper grease. Good Luck J&J JFDI (Just F*****g Do It) Link to comment Share on other sites More sharing options...
alextangent Posted July 20, 2006 Author Share Posted July 20, 2006 5 out of 6 out; but the last bolt in the centre sheared off flush with the head ☹️. The thread on the centre is blind, so the plusgas probably didn't get a chance to get through to the threads. Next move would be to drill a hole and use one of those bolt remover thingies that you screw in? There's not a terrific amount of clearance for a drill (clams) but I should be able to get straight on to what's left of the bolt. Any suggestions? Alex McDonald A loud 1700 SS Link to comment Share on other sites More sharing options...
Normans_Ghost Posted July 21, 2006 Share Posted July 21, 2006 Alex. The "thingies" are Easyouts. Soak some more in Plus Gas and hit fairly hard with hammer and flat ended drift. Drill as near to centre as possible (centre punch the stud to stop the drill wandering). Start with a small drill bit working up to the correct size. Get the easyout well into the drilled hole, or put another way drill in about 3/4". The other method is to keep drilling (for this you must be very close to centre). You will get to the point where you've drilled enough out that only a thin coil is left and if this does not come out of it's own accord it can be taken out with a tap. Use the tapered, 1st cut tap. Norman Verona, 1989 BDR 220bhp, Reg: B16BDR, Mem No 2166, the full story here You and your seven to The French Blatting Company Limited Link to comment Share on other sites More sharing options...
Nigel Riches Posted July 21, 2006 Share Posted July 21, 2006 If they are genuine cap head bolts of the high tensile veriety you'll have trouble drilling the b'stards as they would be hard as the hobbs of hell, may need a drill bit of a harder grade than the usual Jobber kind in your toolbox. Try some more Plus Gas and clouting on the end, wrap a piece of rag soaked in Plus gas around the little sh!t, leave it to soak for a couple of days, giving it whack every now and then, see what happens. 1982. 5 speed, clamshells. B.R.G / Ali. The True Colours. Link to comment Share on other sites More sharing options...
chrisb Posted July 21, 2006 Share Posted July 21, 2006 I managed to get a steering column bolt out using "stud extractors" You only need a smallish hole. The reverse "tap" then screws in teh wrong way. As it is tapered, it gets to the point where something will give. As mentioned previously, heat is your friend. A simple plumbers solder torch (The type that runs in butane) is often enough. Good luck Link to comment Share on other sites More sharing options...
alextangent Posted July 21, 2006 Author Share Posted July 21, 2006 Tried heat, soaked in plusgas and an easyout. Piolot & hole staight an central; then it snapped, B*663R. Now there's a lump of toughened steel in the hole that I now can't get out. Had a premonition this might happen as I did the same on a Dolomite cyl head bolt years ago. This thing is seriously corroded in. The back of the hole isn't blind, but there was that much rust it looked like it. So, is the next step head off and send it to a specialist? Or is there something else I can have a try with first, like a seriously hard drill bit? Depressed because the sun is shining... ☹️ Link to comment Share on other sites More sharing options...
Normans_Ghost Posted July 21, 2006 Share Posted July 21, 2006 Alex, It's happened to all of us. Have you tried following. Centre punch as near to the edge as possible then hit centre punch so it has a turning effect on the stud. I know this sounds daft but the impact of the turning motion can work. It has for me. Norman Verona, 1989 BDR 220bhp, Reg: B16BDR, Mem No 2166, the full story here You and your seven to The French Blatting Company Limited Link to comment Share on other sites More sharing options...
JampJ Posted July 22, 2006 Share Posted July 22, 2006 When you say toughened steel, what did you use to try and get it out? Was it a good quality stud remover? You need a Dormer or Presto. When using heat, you need plenty of it, from an oxy set. If you heat it to a cherry red and let it cool, it should soften the broken metal, and make drilling easier. You could try a 3/16" Dormer TITEX drill bit. Persevere, heat is the answer, but plenty of it, as already mentioned. Good luck, Cheers J&J JFDI (Just F*****g Do It) Link to comment Share on other sites More sharing options...
Unclefester Posted July 22, 2006 Share Posted July 22, 2006 I've found an air wrench is very often the only way to shift cheesy bolts like this, if you have the access. My disc to hub bolts on the rear of the SV were very shallow head, as they appear to have been specially ground down, and the airwrench was the only way I could shift them. NICE PLATE!!! 😬 😬here *eek* Link to comment Share on other sites More sharing options...
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