87Iroc 344 Posted May 27, 2020 Ring end gaps are in spec on top ring. .001 above service limit on 2nd ring(0.021). Looking over the 2nd ring groove, I'm thinking that the binding in the groove was me, though after I removed the jug...as where it was bound may have been where piston made contact with case on one of the rotations I did. I have freed it up now I also checked side clearance. Guessing some carbon build up as I can't get the 0.0015" feeler gauge to go in the groove. Share this post Link to post Share on other sites
shadetree 5,864 Posted May 27, 2020 1 hour ago, 87Iroc said: Fair. I hadn’t noticed that. I wiped it all off with my finger after i read the post. Checking rings now. 2nd ring was bound in groove a bit. this tells me the cylinder is worn, piston '' rubbing '' on that side. i hope the piston did not hit valve, and bend it ?. Share this post Link to post Share on other sites
87Iroc 344 Posted May 28, 2020 (edited) There's no marks on anything indicating impact. The bore has no scars in it. Some lines but you can't feel them with your finger nail. Piston moves freely on the wrist pin and no vertical play in anything. The valve pattern is even all the way both valves after lapping them in this weekend(intake was fine prior to lapping, exh showed carbon and pinhead rust spots but not really any unevenness). My presumption is a compression check would tell me if there's a ring/wear problem as well as any issues with my valve train(thinking of runnign 2. 1 w/adjusted lash, one with it backed off a couple turns per the insp standard). I am OK with dropping a cylinder kit on it if I need to...but figure a compression check is in order before I go that route. I also figure now that the timing is sorted(was fine as we discussed) I could also do this in the chassis pretty easy. Could I do a compression check on the bench? Thinking put head back on it(maybe with old gasket as it seemed to seal fine under 150 psi of compressed air) and spit it over with the starter? For a short spurt, not even sure I'd have to have oil it it...but could throw a couple quarts in it and hook up the oil cooler. ON a side note. Clymer manual has very odd description of ring gap placement. Every SBC I've ever done is 120^ out of phase from the other rings(from memory)....clymer's showed like 60^ out for each one. I did it per Honda manual out there just now. Edited May 28, 2020 by 87Iroc Share this post Link to post Share on other sites
shadetree 5,864 Posted May 28, 2020 3 minutes ago, 87Iroc said: There's no marks on anything indicating impact. The bore has no scars in it. Some lines but you can't feel them with your finger nail. Piston moves freely on the wrist pin and no vertical play in anything. The valve pattern is even all the way both valves after lapping them in this weekend(intake was fine prior to lapping, exh showed carbon and pinhead rust spots but not really any unevenness). My presumption is a compression check would tell me if there's a ring/wear problem as well as any issues with my valve train(thinking of runnign 2. 1 w/adjusted lash, one with it backed off a couple turns per the insp standard). I am OK with dropping a cylinder kit on it if I need to...but figure a compression check is in order before I go that route. I also figure now that the timing is sorted(was fine as we discussed) I could also do this in the chassis pretty easy. Could I do a compression check on the bench? Thinking put head back on it(maybe with old gasket as it seemed to seal fine under 150 psi of compressed air) and spit it over with the starter? For a short spurt, not even sure I'd have to have oil it it...but could throw a couple quarts in it and hook up the oil cooler. ON a side note. Clymer manual has very odd description of ring gap placement. Every SBC I've ever done is 120^ out of phase from the other rings(from memory)....clymer's showed like 60^ out for each one. I did it per Honda manual out there just now. when you checked end gap with rings in cylinder, did you check the top, middle, and bottom with all rings ?. have you checked wrist pin in top of rod for play ?. Share this post Link to post Share on other sites
87Iroc 344 Posted May 28, 2020 Was walking back through this thread. This is what the exhaust valve seat looked like when I pulled the valves. Note how it wasn't hitting on one side....just all carbon with a very fine line of silver elsewhere. My friend never pulled the valves when he had it apart due to the 'skipped timing'. We have lapped them in now so it all looks much better...but wanted to highlight this as I think this is the single biggest issue we found. No sign of bend valves or anything. We chucked them up in a drill. I'll post back this weekend after I get it back in enough to do a compression test. Share this post Link to post Share on other sites
Fishfiles 20,145 Posted May 28, 2020 Wow Iroc , that is pretty bad condition --- Were you'll able to get a lap all the way around that ??? --- is the stem loose in the guide and the valve floating around ---- I think I would be looking for another head in better condition 1 Share this post Link to post Share on other sites
87Iroc 344 Posted May 28, 2020 11 minutes ago, Fishfiles said: Wow Iroc , that is pretty bad condition --- Were you'll able to get a lap all the way around that ??? --- is the stem loose in the guide and the valve floating around ---- I think I would be looking for another head in better condition Yep, we were able to get it to lap all the way around....I will take a pic but it looked really good when my brother got done with it. We didn't know when we put the springs back in that they had to be oriented(and I didn't have new valve stem seals at the time) so I will be taking it back apart tonight and will be checking it closely. I also plan on checking the valve springs per the book for overall length to see if they need replaced. I don't recall a lot of slop in the valve guide as I did check...but will look at it again. The whole cylinder was carbonned up pretty bad. Wondering if maybe the rings aren't quite doing as good a job as they should anymore(per previous conversations in this thread)... along that train of thought, I also plan to pull the jug back off and will recheck the rings in 3 spots to see what they look like. Figure I'll still put it back together and do a compression test....but if need be will pull it apart and oversize it and have the head gone through. Thanks, Greg Share this post Link to post Share on other sites
87Iroc 344 Posted May 28, 2020 (edited) 10 hours ago, Fishfiles said: Wow Iroc , that is pretty bad condition --- Were you'll able to get a lap all the way around that ??? --- is the stem loose in the guide and the valve floating around ---- I think I would be looking for another head in better condition Soooooo. About that. pulled head apart tonight. Exhaust valve to guide is shot. I measured on valve edge at minimum lift to get a measurement .022” of movement. I do not have tools to measure ID and OD. That was with a dual indicator. To confirm a ‘feel’ I did same thing on intake. Negligible movement. I have been pricing heads since this morning off and on. Seems like a new Honda head is 228 or so cheapest I have seen from a Honda dealer on eBay. Seen as high as over 300 from places like partzilla. I would then need springs and valves and keepers. it feels though like new is a better option as online head rehab shops want a fortune and I’d be in to a head as much as a new one to get it rehabbed. EBay is a joke fore used heads what do you guys recommend? i am going to keep reassembling now and try it as in car world the new seals I just put on would gain me a bit of riding before a head replacement is required. Give me time to collect parts. rings and cylinder in my opinion is tired and i think whole Upper engine is in need of a rebuild but head is first priority. Rings will tell their story with compression test. Upper ring was right at service limit for replacement mid cylinder. Middle ring was about ..004” over service spec I believe. Edited May 28, 2020 by 87Iroc Share this post Link to post Share on other sites
Fishfiles 20,145 Posted May 28, 2020 -----if I needed serious head work I would call G+H , they can do complete head work , they use to charge $155 for a head job and that would included what ever is needed , value guides , valves , springs , etc ---- you got a 450 right , you can stick a 400 head on top of it and get some more compression , everything between a 450 and 400 head are the same except the combustion chamber on a 400 is smaller , my 2000 450 has a 400 head 1 Share this post Link to post Share on other sites
Fishfiles 20,145 Posted May 29, 2020 They don't have the 450 listed on there site , you have to call on it , most are still around $160 , I lied , they don't include the guides or springs any more , this is what they say on head rebuilds You mail in your old head to us, and we'll remanufacture it and send it back to you ready to bolt on and go for a quick and easy top end rebuild. PLEASE NOTE: you will be required to mail in your old cylinder head so we can machine it. Here's what's included with this remanufacturing service: Your head will be hydrosonically cleaned and beadblasted. We will then check the guides to make sure they are in spec, and we will measure the spring free length to make sure they've not collapsed. 90% of the time the valve guides and springs are within spec and still good so they are reused. We do, however, tumble clean all the parts so they come out very clean and look like new. If, however, your head needs new guides or springs, there will be an additional charge for these items. We will re-cut valve seats and install NEW valves and NEW valve stem seals. We will lap in the valves and the final step we vaccuum pressure check the head to make sure the valves are sealing properly. Let's face it. All machine work is not equal. When it comes to machining, you get what you pay for. We invest the time in every remanufacturing service we offer to provide only the highest quality workmanship to very strict tolerances making our machine work second to none. We have shops all around the world that rely on us every day to provide them with the quality machining they've come to expect over the years. The machining you receive will be to the same quality standards. Share this post Link to post Share on other sites
87Iroc 344 Posted May 29, 2020 (edited) That’s not a bad deal to get valves for that price. Even if I have to buy guides. I had new hardware on order anyway anticipating there may be issues but not valves. I will call them when I decide it’s time to replace head. Wanna see if my fix is on right path first. it’s a 450 thanks!! Edited May 29, 2020 by 87Iroc Share this post Link to post Share on other sites
87Iroc 344 Posted May 29, 2020 Quick response from G&H. Head machining is 170 as above Guide if needed is 55 per guide Guides are around 15 each. so 250ish for me and I’d have a new head as I assume guide is shot. 1 Share this post Link to post Share on other sites
shadetree 5,864 Posted May 29, 2020 just a thought here bro, why not just buy new valve guides, and replace them yourself ?. all you need is a shop press, some new or used valve guides, presto..done !. i may have a lead on a used head for a 450 at my buds place, i'll see if he still has it ?, if he does, i'll see if i can get it from him for cheap if you want it ?. if he still has it ?, i'll '' pre-assemble it '' for ya, then get it to ya, then all you need to do is bolt it on. if you want to just go your route, thats cool too, i'd just like to save you some cash :-). 2 Share this post Link to post Share on other sites
87Iroc 344 Posted May 29, 2020 28 minutes ago, shadetree said: just a thought here bro, why not just buy new valve guides, and replace them yourself ?. all you need is a shop press, some new or used valve guides, presto..done !. i may have a lead on a used head for a 450 at my buds place, i'll see if he still has it ?, if he does, i'll see if i can get it from him for cheap if you want it ?. if he still has it ?, i'll '' pre-assemble it '' for ya, then get it to ya, then all you need to do is bolt it on. if you want to just go your route, thats cool too, i'd just like to save you some cash that would be awesome! Like I said I have new hardware but not valves coming. I can assemble it here myself but if you need hardware Or valves I could drop ship to you. Let me know what you find. Thanks! Share this post Link to post Share on other sites
87Iroc 344 Posted May 29, 2020 Back in enough to crank. 100 psi Compression with no exhaust or intake on it Share this post Link to post Share on other sites
87Iroc 344 Posted May 30, 2020 Back together. Still the same. compression bumped to 105 psi with exhaust and air filter in place. Carb clean showed no difference in running I have now put a carb kit in the old carb that came with quad(had new eBay unit on it) no change. checking spark it almost seems intermittent spark dropping out. I have an in-line one that lights up. Runs fine and lights fine then quits lighting then lights a couple more times then it dies. I need to confirm tomorrow. it has new CDI box(Honda) and new harness and new stAtor and new pickup beside stator. I am curious how this thing grounds right now. Ran out of steam today. Will do more work tomorrow. Share this post Link to post Share on other sites
Fishfiles 20,145 Posted May 30, 2020 105psi and it is trashed , your wasting time , messing with any thing else , till you fix that problem Share this post Link to post Share on other sites
87Iroc 344 Posted May 30, 2020 (edited) 105 psi is w/in the spec according to Honda with the decompression cam in place? I am not backing the rocker off to bypass that with that reading. I think Honda spec is 70-120 psi with the cam activated(which I assume it is when cranking) Quite possible I am missing something though. Edited May 30, 2020 by 87Iroc Share this post Link to post Share on other sites
Fishfiles 20,145 Posted May 30, 2020 thats right you got a 450 , thinking 300 Share this post Link to post Share on other sites
87Iroc 344 Posted May 30, 2020 (edited) 20 minutes ago, Fishfiles said: thats right you got a 450 , thinking 300 Quote OK. Phew. I'm not afraid of putting a new top end on it...but would rather wait a bit if possible. My plan tomorrow -Keep adjusting fuel down(brother suggested this as he thought it might be getting too much fuel as carb clean had no impact. I started at pilot out 2 turns. Down to about 1 1/4 now with no change really) Will put back to 2 turns out if no change is seen. -Run compression with exh rocker backed off 2 turns. -Confirm the spark phenomenon I mentioned. -Confirm plug heat range is to spec(plug looks new). -Trace ground wires/ignition wiring to see if a ground is loose or something -Start through Honda trouble tree essentially. Edited May 30, 2020 by 87Iroc Share this post Link to post Share on other sites
87Iroc 344 Posted May 30, 2020 I'm just brainstorming sitting here tonight things that might cause an intermittent spark failure knowing all the stuff my friend replaced(Assuming all is good and something isn't fried) and saw reference to an engine kill switch on the handlebars. My multi-switch on left grip is wiped out and I can't tell looking at it what the different switches do. But downloaded the owners manual and I see it. I know I have flipped switch messing around....but do those things ever go bad? Thinking like an intermittent grounding due to 22 yr old switch? It is NOT new... Testing says to find connector check for continuity....but if its an intermittent' shaking' thing possible it only happens when running? ANyway just brainstorming. Share this post Link to post Share on other sites
87Iroc 344 Posted May 31, 2020 Short update for those still reading... I turned the pilot screw in all the way until it stopped moving. Engine ran the same. It shouldn't run at all I don't think with it turned in. I then started looking at the starter enrichment valve. The thing is very rough. O-ring seal is non-existent(collapsed completely) and spring was broken/bent. So I have a new one on order. I tried doing a couple other things. Putting o-ring on needle end and pushing it with my finger to seal off any fuel(it is currently disconnected from the cable obviously)...but really saw no difference(felt vacuum on finger as I pushed down and sealed the chamber but when it blows back after it shuts down occasionally it will pop it out of the hole). Turned pilot screw back out 2 turns(book says 2 5/8 now that I'm reading it). Still no difference. Now It appears starter solenoid has given up the ghost. Not surprising as its been abused lately. I tried starting it a few times by jumping the terminals for now. Hopefully that doesn't tweak anything else in the system. I also checked the kill switch and rechecked the spark. I think that was a dead end. Switch does its thing fine and the spark appears to follow flashing as it should. No 'few revolutions w/o spark' like I thought last night. I also took off all the grounds I could find and buffed paint off and put them back on to ensure it had what it needed to function. Chasing fuel for now as w/everything off it still seams to flood(when pull carb after failed start the downstream area is soaked with fuel) and it doesn't respond to carb clean at all...will see. Share this post Link to post Share on other sites
LedFTed 1,127 Posted May 31, 2020 On 5/29/2020 at 9:24 PM, 87Iroc said: Back together. Still the same. compression bumped to 105 psi with exhaust and air filter in place. Carb clean showed no difference in running I have now put a carb kit in the old carb that came with quad(had new eBay unit on it) no change. checking spark it almost seems intermittent spark dropping out. I have an in-line one that lights up. Runs fine and lights fine then quits lighting then lights a couple more times then it dies. I need to confirm tomorrow. it has new CDI box(Honda) and new harness and new stAtor and new pickup beside stator. I am curious how this thing grounds right now. Ran out of steam today. Will do more work tomorrow. was the carb ever from eBay? Share this post Link to post Share on other sites
87Iroc 344 Posted May 31, 2020 New carb he gave me was an eBay or something. Had reviews it worked fine. Old carb is not factory carb(no air shut off on side). I took that old one and put a carb kit in that shade tree recommended. I had never done a carb before but sprayed every orifice I could find with carb clean. Share this post Link to post Share on other sites
87Iroc 344 Posted June 3, 2020 (edited) Ran a compression tests today finally w/decompress-or deactivated. Not sure why I didn't do it sooner....just chasing the fuel issue still. Decompress-or Active: 105 psi Deactivated(Dry Cylinder): 155 psi Deactivated(Squirts of oil): 190/180/170/170 Spec for this is 178-206 psi So it seems like rings are tired....but is that low enough for it not to idle for a long time or accelerate at all? I have not received my starting valve(choke plunger) to test. Supposed to be here yesterday. Appears to be lost in transit. Thanks, Edited June 3, 2020 by 87Iroc Share this post Link to post Share on other sites