headdamage Posted March 5, 2008 Share Posted March 5, 2008 I've got a 200tdi that I can not remove the #1 piston from the cylinder. The big end of the con rod seems to be too wide to fit, I assume the con rod is bent, I don't know what else could cause this problem. How the heck do I get this out? Right now the crank is still in the block, if I remove it can I get the piston out of the bottom? Thanks for any help. Quote Link to comment Share on other sites More sharing options...
Les Henson Posted March 5, 2008 Share Posted March 5, 2008 If it was that bent I should think you would be able to see it. Are you sure it's not the rings preventing the piston from coming out because they are catching on the carbon strip around the top of the bore? If the rod is that bent, then removal of the crank/oil spray jets will allow it to come out the bottom I should think - never had to do it that way though. Les. Quote Link to comment Share on other sites More sharing options...
muzaz Posted March 5, 2008 Share Posted March 5, 2008 I dont think the piston and rod assy can come out of the bottom end even if you take the oil jet away...the way I see it if you dont want to take the crank out, try to push up the piston as far as possible and take the gudgeon pin out to take the piston off...then take out the conrod from the bottom...well try to bec I'm not sure you'll be able to Quote Link to comment Share on other sites More sharing options...
muzaz Posted March 5, 2008 Share Posted March 5, 2008 Just had a look at my tdi which is still in a hundred pieces.... it looks like it will be a hell of a job if the conrod is bent, there's no way the piston will come down the bottom, and if the rod is bent it wont come up far enough to take the gudgeon pin out! The only way I can see it is to take the crank out, take the oil jet out, push the piston down as far as it will, and grind/saw off the bottom end of the conrod.... then take the piston and whats left of the conrod from the top... but first make sure its a bent rod like Les said....when I took mine off one piston wouldnt come off, found an oil ring broken which was binding a bit in the bore.. chris Quote Link to comment Share on other sites More sharing options...
headdamage Posted March 5, 2008 Author Share Posted March 5, 2008 It's not the rings because I could get it out enough to clear all three and I've taken them off of the piston now. The piston moves very freely in the bore now but the rod binds up just as the last mm or so of the bit end tries to enter the bore. From the bottom it looks like the big end is 1 or 2mm too wide to fit up the bore. It also doesn't look like the piston can come out of the bottom due to the block webbing so I thinki I have to either make the big end a bit narrower or cut it off. Either way my quick engine swap has turned into a full on rebuild project. At least now I'll become very familiar with the tdi, all I've worked on before where 2.25P and 2.5na diesel engines. Quote Link to comment Share on other sites More sharing options...
disco_al Posted March 5, 2008 Share Posted March 5, 2008 can you remove the oil jet, move the piston as far down the bore as possible then get the gudgeon pin out? if you can do that, then you may end up with enough clearance to remove the rod through the top. Quote Link to comment Share on other sites More sharing options...
muzaz Posted March 5, 2008 Share Posted March 5, 2008 no he wont be able to, theres no space at the bottom... Quote Link to comment Share on other sites More sharing options...
upnover4x4 Posted March 5, 2008 Share Posted March 5, 2008 Kind of drastic I know,.... is there any way you can cover the crank journals etc & cut thru the conrod with a hacksaw. Maybe worthwhile unbolting all conrods & sliding the pistons up the bore, then you can clean the journals easier.Plug the oilways or tape overthem. As long as you give the bottom end a good clean after cant imagine there would be that much debris. Beats the cra.. out of taking the bottom end out. Adrian Quote Link to comment Share on other sites More sharing options...
headdamage Posted March 5, 2008 Author Share Posted March 5, 2008 I'm going to take the crank out anyway now... thing are looking too sketchy in there for me to trust this engine without doing a full on rebuilt with the block and crank getting checked out at a machine shop and machined as needed. I'm likely going to try nad hack off one side of the big end once the crank is out of the way so that it will go up the bore. Quote Link to comment Share on other sites More sharing options...
headdamage Posted March 6, 2008 Author Share Posted March 6, 2008 I finished stripping the engine tonight and cut one side of the big end off with a hack saw. Piston and rod are out and on the bench... the bend is easy to see now that it is out of the block. Quote Link to comment Share on other sites More sharing options...
western Posted March 6, 2008 Share Posted March 6, 2008 Don't be shy, lets see it Quote Link to comment Share on other sites More sharing options...
headdamage Posted March 7, 2008 Author Share Posted March 7, 2008 The bore looks good... will try to measure it this weekend to be sure. Dropped the crank and head off at the machine shop and the injection pump, injectors, and turbo off at the diesel shop. I'll try to get some pics of the rod. Quote Link to comment Share on other sites More sharing options...
Lara Posted March 7, 2008 Share Posted March 7, 2008 The bore looks good... will try to measure it this weekend to be sure. Dropped the crank and head off at the machine shop and the injection pump, injectors, and turbo off at the diesel shop. I'll try to get some pics of the rod. Why bother measuring the bore? For the price of a set of pistons and a rebore you may as well just do it now the motor is apart! you will only kick your self later if you don't. Lara. Quote Link to comment Share on other sites More sharing options...
headdamage Posted March 7, 2008 Author Share Posted March 7, 2008 Why bother measuring the bore?For the price of a set of pistons and a rebore you may as well just do it now the motor is apart! you will only kick your self later if you don't. Lara. Why would I want to re-bore it if it is in spec for standard pistons? If if is in spec seems like honing it and putting new rings on the standard pistons would be the better idea. Quote Link to comment Share on other sites More sharing options...
Les Henson Posted March 7, 2008 Share Posted March 7, 2008 Set of gen pistons will set you back the painful side of £230, and a rebore around the £120 mark. Assessment of bore wear is the decider. I occasionally just replace the rings, or fit new same size pistons. There is a certain element of risk - that is why the bores have to be checked very carefully. Les. Quote Link to comment Share on other sites More sharing options...
Lara Posted March 7, 2008 Share Posted March 7, 2008 Do know what you both mean but to be honest, 350 quid to know you have brand new stuff in perfect condition is well worth it! And just have a little think as well on the points here. 1. your engine we have to assume was built originally with the correct tolerances etc, 2. to do the job correctly you need to machine hone it and not just throw a ball hone down the bores, 3. If you do that, it will undoubtedly increase the piston to wall clearance from what was originally the correct size, OK maybe only a though or so but still, 3a. therefore it stands to reason that it will never be quite as good as going the whole hog, may be good enough but who wants "good enough" when you can have "perfect" for an extra 350! Of course that is, if you have 350 to spare, and I accept that not everyone does. Lara. Quote Link to comment Share on other sites More sharing options...
Les Henson Posted March 7, 2008 Share Posted March 7, 2008 I thought my engine might only cost a couple of hundred or so quid, but in the end it's nearer £900 Les Quote Link to comment Share on other sites More sharing options...
Lara Posted March 7, 2008 Share Posted March 7, 2008 I thought my engine might only cost a couple of hundred or so quid, but in the end it's nearer £900 Les Isn't that always the way And we wonder why we are always skint Lara. Quote Link to comment Share on other sites More sharing options...
muzaz Posted March 7, 2008 Share Posted March 7, 2008 3. If you do that, it will undoubtedly increase the piston to wall clearance from what was originally the correct size, OK maybe only a though or so but still, was of your same opinion...until I did mine....and found out that the amount of material taken of by honing is negligible, infact when I measured the inbore clearance of the rings, I measured 1thou less than the miniumum allowed!! well the clearance will increase as the rings bed in, so it should be ok. So my IMHO I'd change all that really needs to be changed...like the con rod in this case etc...but try to contain the costs to keep it feasible chris Quote Link to comment Share on other sites More sharing options...
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