johnvica Posted February 15, 2011 Report Share Posted February 15, 2011 I need help. I am putting together this 5K which I have been told the head is also from a 5K. The motor and head have had work done to it. I don't know alot hence I have put pics that can be seen on the below web page. On he piston it has .40 on it. I assume bored 40thou over. Can anyone tell me by looking at what I have, WHAT I HAVE? (I know stupid question..) Also the motor has also been striped a few times since being built- 1st time bent rods hence vale marks on the pistons. 2nd time (now) blown head gasket. Looking at the head and block I note that the water ports don't all line up, I think there are 3 (2 in the front of the block and I think the other in the rear). Is this normal? Also with the head gasket, all the water ports did not have openings on it. I would assume/thought that the head gasket would come with all the required cut outs (holes) in the gasket - not just a portion of them? I have another issue on the car (KE20) the gearbox (5 speed) on the back of the 5k.. I have no clutch pedal. The clutch kit and flywheel were taken to were I bought the clutch and apparently thats all sweet, there is basically a big gap between the throw bearing and pressure plate (fingers). I did attempt to unscrew the pivot bearing on the folk and it did work abit, but want to do it right. Any thoughts here as well. Thanks everyone for reading any help is greatly appreciated. Quote Link to comment Share on other sites More sharing options...
altezzaclub Posted February 15, 2011 Report Share Posted February 15, 2011 Well, you've got a nice set of side-draughts! I assume the motor was running OK, so everything should work when replaced. However reading the history of it I would feel worried that it was not engineered properly to start with. Have you had the head checked for flat? Did it blow into the water jacket on number 1? Where the photo is dirty? That would be a bit odd.. Number 3 looks marked too, and is that a burn mark on number 4 in the other photo?. A simple problem like not checking the bolts screwed all the way down would stop it torqueing down correctly. The marks in the pistons look like the head that was on there was the wrong head (too low) or had a big cam that was not timed correctly. Its not that you've been sold a pup, but I can hear barking... :laff: There are several heads for 5Ks, and that one may not match the block. Before you assemble it, put the head on without a gasket, fit the rocker gear and turn it over by hand with no spark plugs. If you feel the valves hit a piston you have a problem. The 5K experts can tell you which head it is, but I can tell you the jacket holes being dead ends is normal and designed to equalise the heat distribution through the water flow. Quote Link to comment Share on other sites More sharing options...
johnvica Posted February 15, 2011 Author Report Share Posted February 15, 2011 Thanks for the response. the motor was - is running.. Just got a blown head gasketnow. The first time it was put together wrong (timing) hence the markings on the piston. I note the water jackets - thatnks. Just with the head gasket, should all the holes be all there or only a portion of them as like the one I pulled off it. I will post it on the above link. Quote Link to comment Share on other sites More sharing options...
altezzaclub Posted February 15, 2011 Report Share Posted February 15, 2011 Head gasket might vary according to manufacturer, but the excess holes that are there do nothing against a blank face anyway, so it doesn't matter. So long as you have holes in the gasket where you have holes matching in the block and head. Where did the gasket fail? Quote Link to comment Share on other sites More sharing options...
Felix Posted February 15, 2011 Report Share Posted February 15, 2011 I'd say your motor started as the most common D dished 5k: Deep D dished pistons and a shallow combustion chamber head (identified by 2 big lugs under no 1 and 4 spark plug holes). The problem is there are no aftermarket pistons available to suit. The only ones available are shallow dished pistons which seriously up the compression and can lead to valve/piston clearance issues. What you need is a head from a flat top piston 3k or 4k. These have a deeper combustion chamber and will restore your CR. The problem you will then most likely face is pushrod length as these heads are taller. Search the forum and you will find info on pushrods for 5k's. Quote Link to comment Share on other sites More sharing options...
altezzaclub Posted February 15, 2011 Report Share Posted February 15, 2011 Thankyou Felix- I thought it would be a mis-match like that but I've never dealt with 5Ks. Do we have a central link for this info? Something that explains and photos the various 5K motors. The Wiki doesn't seem to cover it. Quote Link to comment Share on other sites More sharing options...
snot35 Posted February 15, 2011 Report Share Posted February 15, 2011 I have to backup Felix here, that very much looks like a D dish head. I have one also and there is a hell of a lot more space in the crown of the piston. Your current setup is probably up around 12 or 13:1 (wild guess) compression. Good luck getting that to run on just about any readily available fuel without blowing a bunch of gaskets. Quote Link to comment Share on other sites More sharing options...
camerondownunder88 Posted February 16, 2011 Report Share Posted February 16, 2011 Hi, You can STILL buy deep dish 5k pistons I can get them new from my engine builder who is building my 5K atm original size 20 and 40 and 60 thou over sized. PM me if you need his number to order some. But when it blew had you reved it hard? Could possibly been a bit of valve bounce and hit the pistons??? Cheers Cameron Quote Link to comment Share on other sites More sharing options...
philbey Posted February 16, 2011 Report Share Posted February 16, 2011 I have to backup Felix here, that very much looks like a D dish head. I have one also and there is a hell of a lot more space in the crown of the piston. Your current setup is probably up around 12 or 13:1 (wild guess) compression. Good luck getting that to run on just about any readily available fuel without blowing a bunch of gaskets. Keep going on that figure. I had 9cc dish (ACL aftermarkets) vs the 22cc factory deep dish, and that was static comp ratio of 12.1:1 A big cam got me out of trouble. Your pistons in those pics have almost no dish it appears so you could be pushing even higher. Quote Link to comment Share on other sites More sharing options...
Andy43 Posted February 16, 2011 Report Share Posted February 16, 2011 (edited) Here's some stuff I posted on push rod lengths. http://www.rollaclub...__1#entry450919 If you need some 4k ones PM me you can have them. If you retard the cam the compression pressures will be reduced and hence it may run on pump gas, I aggree good cam choice may be a option. Cheers Andy Edited February 16, 2011 by Andy43 Quote Link to comment Share on other sites More sharing options...
altezzaclub Posted February 16, 2011 Report Share Posted February 16, 2011 Before you reassemble it make sure you measure the head volume and the piston dish volume and calculate the compression ratio. You can always run two gaskets or a steel spacer to drop it. Quote Link to comment Share on other sites More sharing options...
johnvica Posted February 16, 2011 Author Report Share Posted February 16, 2011 Yes the motor has been basically just put together without any engineering or advice such as from this forum. BACKGROUND: My bros car and he has taken it to a mate to put it together, so big bro here to help.. I know it has a big cam in it. 1st time it was put together the timing chain was put on wrong hence the bent vavles. Now with the head gasket blowing, apparentlly it over heated on the first run out. Based on what I have read above, the set up doesn't seem great due to high CR given the "flattish" pistons?? But a big cam might get me out of trouble. ummmm, issues with a high CR is blown gaskets, less power? is that right? How can you check compression ratios? I might put it back together and see how I go given the overheating when it was first taken out. Now with the head gasket, point taken with openings not lining up with no water jackets, but if there is no opening on the gasket where water jackets line up, what can you do to the gasket? just put an opening in it or would this stuff up the gasket? Quote Link to comment Share on other sites More sharing options...
philbey Posted February 16, 2011 Report Share Posted February 16, 2011 A big cam won't help. I have a damn big cam for a street car and I only just got away with it. Your static compression will be much higher. Look up a compression ratio calculator on Google. You need to measure the volume of your head, volume of piston, piston crown Dia, piston at ring land Dia, bore dia, piston to deck height, head gasket dia and compressed gasket thickness, crank stroke. Feed into a calculator to determine static comp ratio. Aim for 10:1 to 11:1. Your overheating and gasket issues are from pre ignition from high comp. I bet this thing sounds horrible when its running? Best you look for either new.head or need piston. Piston will be 160 brand new from acl. Sorry about limited response I'm on the HTC not the computer. Quote Link to comment Share on other sites More sharing options...
altezzaclub Posted February 16, 2011 Report Share Posted February 16, 2011 but if there is no opening on the gasket where water jackets line up, what can you do to the gasket? just put an opening in it or would this stuff up the gasket? hmm.. in theory that shouldn't happen, the holes should be in the right place. However... what gasket do you buy if you have a mongrel engine made up of two different ones to start with?? You measure head and piston dish volumes with a piece of rigid plastic and a burette or pipette full of turps, as shown in here.. http://www.rollaclub.com/board/topic/42407-the-girls-ke70/page__p__445727__fromsearch__1#entry445727 Its not difficult. Quote Link to comment Share on other sites More sharing options...
johnvica Posted February 17, 2011 Author Report Share Posted February 17, 2011 Does any1 know where I can get a spacer for the head? Quote Link to comment Share on other sites More sharing options...
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