Possible bent valves from turning crank pulley?
I have a problem with my stock 89 CRX Si. I was trying to break loose my crank pully, but the screwdriver kept slipping on the flywheel teeth. I had the cam gear off, so the valves were all staying put while the crank was turning.
Well I realized that the cam was about 50-80 degress past TDC. I had spun the crank over several times by hand before I realized it. I had noticed the crank got hard to trun a couple times while turning, but I thought it was just compression. Well it turns out I was pushing the pistons against the valves. My question: Is it possible to bend or damage my valves by hand turning the crank? I really don't know how delicate these parts are. CURSE YOU CRANK PULLY!!! |
Re: Possible bent valves from turning crank pulley? (94eg!)
I guess it would be possible, I doubt that it actually happened. I had a similar issue and I had similar concerns (I torqued the head down while the block was at TDC and the head was in a random spot). It ended up starting perfect and passing smog that week. I wouldn't worry too much in your situation, just make sure its timed in, torqued down, and everything is hooked up https://honda-tech.com/forums/images/smilies/emthup.gif
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Re: Possible bent valves from turning crank pulley? (ProjectDarkBlack)
Well that's some relief. I can't put the thing back together until I get a new cam seal, so I'm just gonna be sweatin it until then. Thanks for your input & experience...
Any other opinions or experiences are welcome (of course)... |
I did this on a 528e and thought I was at tdc when in fact I was 180 Degrees out when installing the timing belt. I remember it getting hard to turn and thought it was compression but realized I had the plugs out. Figured out he problem, put it back together and it fired up just fine. I was lucky but remeber, these are interferance engines. It is totally possibly you bend a valve so don't rule it out. An easy way to check if you have the head off is to lap the valves. Use marking compound and check the pattern on the face of the valve to the valveseat. If its uneven you have a bent valve. Actually an easier way to check is to set the head upside down and level and pour gas into each chamber and see if it holds (make sure cam is off and all valves fully seated). If any drain out, you probably have a bent valve. Check for marks on top of the piston where a valve may have made contact and check those valves.
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Re: (statik121@hotmail.com)
None of us really know but I'd bet my left nut you'll be ok
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Re: (mahatma)
Well, I'm comin to collect if it's not... http://images.honda-tech.com/set1//smile/emcrook.gif
I'll know tomorrow after I the stealership gets my seals in. Wish me luck... https://honda-tech.com/forums/images/smilies/emthup.gif PS: Thanks again for all your guys advice... |
Re: (94eg!)
It's a non-interference engine, the valves won't touch the pistons in stock configuration. This is why you clay a motor when you build it to check valve to piston clearance.
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Re: (CRX7)
Here is a list of known interference engines. I'm not sure, you might want to check the list for oyur engine. What does a noobie know anyways right?
Interference Engines The AERA Technical Committee would like to offer the following information on engines that present the possibility of interference between pistons and valves. The interference or contact may bend valve(s) when timing between the camshaft and crankshaft is interrupted. This is generally the result of a timing belt or chain breaking or slipping. The following list are engines that AERA is currently aware of that have exhibited interference. There may be other engines that are not listed below that have the possibility of piston to valve contact. If the engine you are working on is not listed, do not assume that it is a freewheeling design. It is suggested to add to this listing as additional information is obtained. ACURA 1986-89 1.6L Integra 1991-95 1.7L Integra 1990-95 1.8L Integra 1986-89 2.5L Legend 1992-94 2.7L Vigor 1990 2.7L Legend 1991-95 3.0L NSX 1991-95 3.2L Legend FIAT 1974-79 1.3L 128 Series 1979-82 135L Stranda 1974-78 1.6L 124 Series 1974-78 1.8L 124 Series 1974-78 1.8L 131 Series, Brava 1979-82 2.0L Brava, Spider HONDA 1986-87 1.0L Prelude 1973-78 1.2L All 1973-78 1.3L All 1980-84 1.3L All 1973-78 1.5L All 1985-89 1.5L Civic 1988-95 1.5L Civic,CRX 1993-95 1.5L Civic Del Sol 1973-78 1.6L All 1980-82 1.6L All 1988-95 1.6L Civic, CRX 1984-87 1.8L Prelude, Accord 1979-83 1.8L All 1986-91 2.0L Prelude 1990-91 2.1L Prelude 1990-95 2.2L Prelude, Accord 1992-95 2.2L Prelude 1995 2.7L Accord AUDI 1970-93 All Except 1970-77 1.9L & 1970-73 1.8L FORD 1981-85 1.6L Escort, EXP 1981-83 1.6L LN7, Lynx 1984-85 2.0L Escort, Tempo 1993-95 2.0L Probe 1986-88 2.0L Ranger 1984-92 2.2L Lynx, Topaz Diesel 1985 2.2L Ranger 1989-92 2.2L Probe 1986-88 2.3L Ranger 1986-87 2.3L Diesel Ranger 1991-98 4.6L Crown Victoria HYUNDAI 1984-95 1.5L Excel Scoupe 1995-98 1.5L Accent 1992-95 1.6L Elantra 1993-95 1.8L Elantra 1992-95 2.0L Sonata 1989-91 2.4L Sonata 1990-95 3.0L Sonata BMW 1987-95 2.5l 3251 5251 1994-95 4.0L 7401 GM 1986-95 1.0L Geo Metro 1989-91 1.0L Firefly (CANADA) 1985-88 1.5L Sunburst (CANADA) 1985-89 1.5L Spectrum 1990-93 1.6L Prizm, Storm 1981-84 1.8L Diesel (CANADA) 1982-86 1.8L Buick Skyhawk 1990-98 1.9L Saturn 1987-88 2.0L Buick Skyhawk 1988-95 2.3L Quad Four 1985-87 3.0L Buick 1993-94 3.4L Corsica 1979-95 3.8L Buick PORSCHE 1976-83 2.0L 924 1976-89 2.5L 944 Series 1989 2.7L 944 Series 1989-91 3.0L 944 Series 1976 4.7L 928 1984 4.7L 928 1985-91 5.0L 928 1992-95 5.4L 928 DAIHATSU 1988-92 1.0L Charade 1988-92 1.3L Charade 1990-92 1.6L Rocky INFINITI 1990-92 3.0L M30 KIA 1995 2.0L Sportage ISUZU 1987-89 1.5L I-Mark 1990-93 1.6L Stylus Impulse 1987-89 2.0L Impulse 1981-87 2.2L Diesel Truck 1986-95 2.3L Truck Trooper 1988-95 2.6L Truck Rodeo Amigo 1991-96 Trooper Rodeo Amigo MAZDA 1984-85 2.0L 626 1988-92 2.2L 626 MX6 1989-93 2.2L Pickup 1988-95 3.0L 929MPV SUZUKI 1985-94 1.3L Samurai Sidekick 1989-94 1.3L Swift TOYOTA 1986-95 1.5L Tercel 1981-83 2.2L Pickup 1984-87 2.4L Pickup 1982-88 2.8L Celica Cressida 1987-94 3.0L 4-Runner MITSUBISHI 1985-95 1.5L Mirage Precise 1990-92 1.6L Mirage 1989-95 2.0L Galant Eclipse 1983-86 2.3L Diesel Pickup 1994-95 2.4L Galant NISSAN 1982 1.5L Centra 1983-88 1.6L Sentra Pulsar 1987-89 1.8L Pulsar 1982-89 2.0L Stanza 300ZX 1984-95 3.0L Maxima 300ZX Pathfinder VOLKSWAGEN 1976-91 All Except 1.9 2.1L Engine 1990-92 1.6L Golf(CANADA)Jetta 1990-95 2.0L GTI Jetta GLI Passat |
Re: (CRX7)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by CRX7 »</TD></TR><TR><TD CLASS="quote">It's a non-interference engine, the valves won't touch the pistons in stock configuration. This is why you clay a motor when you build it to check valve to piston clearance.</TD></TR></TABLE>
It is an interference engine, and that is not the reason why you clay-check a motor. How would clay-checking the engine work if you cannot spin the motor over because of piston valve contact. Your suposed to clay-check the motor to see the minimum valve to piston clearance during normal rotation (with the timing belt on). This way you can tell if your cam leaves enough of a margin-of-error for slight valve float or rod stretch. The valves are never fully extended while the piston is at TDC... |
Re: (94eg!)
I was wrong. So why do you clay a motor?
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Re: (statik121@hotmail.com)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by statik121@hotmail.com »</TD></TR><TR><TD CLASS="quote"> Actually an easier way to check is to set the head upside down and level and pour gas into each chamber and see if it holds (make sure cam is off and all valves fully seated). If any drain out, you probably have a bent valve. </TD></TR></TABLE>
Thats not an accurate way of checking. I just went through this with a type R motor that had ALL its exhaust valves bent. Every chamber held fluid http://images.honda-tech.com/set1//smile/emcrook.gif . <TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by CRX7 »</TD></TR><TR><TD CLASS="quote">So why do you clay a motor?</TD></TR></TABLE> To see how much piston to valve clearance you have when dealing with high compression pistons and or high lift cams or even a milled head/deck. To the OP: Hopefully your valves are OK. It can be fairly easy to bend valves. Only sure way is to fire it up, see how it runs, and do a compression check to confirm. |
Re: (fourthgenhatchB17)
How long did you wait? 5 maybe 6 minutes? I recommend letting it sit overnight. I probably should have posted that in the first message (my bad). As far as being accurate, its common practice to fluid check a head for bent valves. See it done in my shop all the time done by veteren techs. Lapping valves is a good, easy and accurate method. If you want to get real accurate, whip out your handy dandy dial indicator with a holding fixture and check each valve (assuming you know how to use a dial indicator of course). Fuckit.... Take it to a machine shop and shell out the $50 to get it look at if your that worried.
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Re: (statik121@hotmail.com)
The valves have to be significantly bent to leak fluid. I mean on cylinder 1 and 4 i still got 220 psi and cyl. 2 and 3 were much lower but still held fluid. I didnt wait overnight...i just didnt have the time. So in conclusion, the fluid trick might not reveal the slightest of bends.
Anyways, good luck to the OP https://honda-tech.com/forums/images/smilies/emthup.gif . I wanna know the outcome. |
Re: (fourthgenhatchB17)
Well I got the car back together this evening, and she fired up just fine. I drove it carefully and didn't notice any ill effects. After getting some balls up, I gave it some gas to see how she felt. I couldn't tell any difference in performance since the incident. I did notice that the valve-train was making a bit more noise than before. I'm gonna have to do a compression check and valve lash adjustment tomorrow.
I don't know if it makes any noise difference, but I am currently running the car without the upper timing cover (perhaps it makes more noise that way). My plan is to modify the timing covers lip so I can pop it into place without taking off the valve cover. I'm not really comfortable reusing valve cover gaskets (I'm trying to reduce the leakage), and I just installed a new one with plug seals. This project was just supposed to be a cam-seal replacement that I was trying to turn into a timing belt/water pump replacement. I'm not quite ready to take a cylinder head off yet, so I can't take it in to have it checked out... Thanks again for everybody's help. I'll keep you up to date... |
Pfft i touched them lots of times whenever i done timing belt replacements and water pump replacements on all kinds of honda motors. Everytime i did it, it was harder because they bumped each other but then they clear once you turn it over again anyways, so yes they touch but then they clear ifyou keep going anyways. https://honda-tech.com/forums/images...s/emsmilep.gif
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Sorrys that was confusing, lol hope i helped. https://honda-tech.com/forums/images...es/emsmile.gif
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Re: (Contender25)
I'm so pissed right now. The brand new valve cover gasket I installed has a fucking tear in it. I went to do a compression test & swap plugs, so I popped open my hood to find oil sprayed all over my intake manifold & everything else back there. It was running down onto the exhaust & driveway. WTF? Aparantly I only lost about .5 quarts of oil, but it's still retarded. I hope honda will replace it because don't want to spend another $10 on something so stupid...
On the flip side, the cam seal I installed was dry as a bone & the motor is runing nice & smooth. Very happy with that... |
Thats good, it will be alright, won't be bad at all so don't worry.
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Actually, as a tech or a parts customer, you are responsible for inspecting parts to ensure you got the right one and it's not damaged. If it's been installed, they will probably not accept it as a return. It's the same policy as most parts stores.
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Re: (statik121@hotmail.com)
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Re: (fourthgenhatchB17)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by fourthgenhatchB17 »</TD></TR><TR><TD CLASS="quote">
To see how much piston to valve clearance you have when dealing with high compression pistons and or high lift cams or even a milled head/deck. .</TD></TR></TABLE> Right, meaning if the engine isn't running there isn't any overlap since there is clearance. You only have to worry about valves hitting the pistons if it is running. Which is why your need stronger valve springs to avoid valve float so they won't hit the piston. Glad there wasn't a problem. |
Re: (CRX7)
Well I got in there & did a valve lash adjustment and replaced the spark plugs. A compression test showed that I still have good sealing (for 190k miles):
Engine warmed up, injectors disconnected, wide open throttle, 250 rpm (starter motor): #1 = 165psi #2 = 155psi #3 = 163psi #4 = 165psi Nominal = 185psi Minimum = 135psi Max variance = 28psi As for my gasket problem, Honda replaced it without any trouble. I simply told him what happened, and asked if there was any way he could help me out. Pretty cool of them since I know they don't have to do that... My valve-train is quite a bit noiser after the valve lash adjustment. I'm kinda surprised. I reduced rocker arm clearance on almost every valve (except one), so I would think it would make less noise (.008" intake & .010" exhaust) I don't quite know if thats normal. Any insight would be welcome... |
Re: (94eg!)
cool. good to hear no serious damage with the valves.
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