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99 Ody EX, 235K mi - After pulling and reconditioning heads to replace bent intake valve on non-firing cyl 1, now have bent intake valve on non-firing cyl 5 and low compression on cyl 4. Here are the details.
Doing timing belt replacement. Also, pulled vtec solenoid, vtec pressure switch and solenoid/filter assy to replace o-rings. Hand-turned crank 6 times with new timing belt and saw rear cam was 180* off-time from front cam and crank. Removed belt, rotated rear cam back to TDC and re-installed belt. Hand turned crank again, watching belt-tooth position. All OK. When I started engine, it ran rough immediately, with valve chatter on rear head.
Warm engine compression test revealed:
- Cyl 1 - 0 psi
- Cyl 2 - 200 psi
- Cyl 3 - 205 psi
- Cyl 4 - 207 psi
- Cyl 5 - 205 psi
- Cyl 6 - 183 psi
Pulled both heads and sent to machine shop for reconditioning and valve job. Shop replaced stem seals and 2 valves: bent primary intake valve from cyl 1 (vtec intake valve OK); one exhaust valve (probably from cyl 6). Shop said they set intake valve lash at .008” and exhaust valve lash at .010”.
Put engine back together with new head/intake/exhaust gaskets. Hand turned crank with new timing belt, watching belt-tooth position. With plugs out, crank and cams turned easily, with no obstructions. But, when I started engine, it ran rough immediately, with valve chatter on front head.
This time, warm engine compression test reveals:
- Cyl 1 - 183 psi
- Cyl 2 - 182 psi
- Cyl 3 - 181 psi
- Cyl 4 - 130 psi
- Cyl 5 - 0 psi
- Cyl 6 - 185 psi
Valve lash after compression test:
- Cyl 4 - Both intake valves at .011”; both exhaust valves at .010”
- Cyl 5 - Vtec intake valve at .008”; primary intake valve lash too large to measure (bent valve); both exhaust valves at .011”.
- Cyl 6 - Vtec intake valve at .009”; primary intake valve at .024”; both exhaust valves at .025” - but compression is fine.
Plan to pull front head and replace any bent valves. I don't want to do this again, so I would like to understand the cause of these problems: low compression on cyl 4, bent valves on cyl 5, and large valve lash on cyl 6. Possible causes:
- Could be something with vtec system, since I removed/reinstalled pressure sensor and solenoid.
- I may have bent the cyl 5 intake valve when I set the front head. When I set the heads, the crank was at TDC, with cyl 1 and cyl 5 at the top of their stroke. Before I set the heads, I rotated the cams about 60* from TDC, so there wouldn’t be any fully open valves. But, the cyl 5 valves may not have been fully closed.
I would appreciate any advice.
Doing timing belt replacement. Also, pulled vtec solenoid, vtec pressure switch and solenoid/filter assy to replace o-rings. Hand-turned crank 6 times with new timing belt and saw rear cam was 180* off-time from front cam and crank. Removed belt, rotated rear cam back to TDC and re-installed belt. Hand turned crank again, watching belt-tooth position. All OK. When I started engine, it ran rough immediately, with valve chatter on rear head.
Warm engine compression test revealed:
- Cyl 1 - 0 psi
- Cyl 2 - 200 psi
- Cyl 3 - 205 psi
- Cyl 4 - 207 psi
- Cyl 5 - 205 psi
- Cyl 6 - 183 psi
Pulled both heads and sent to machine shop for reconditioning and valve job. Shop replaced stem seals and 2 valves: bent primary intake valve from cyl 1 (vtec intake valve OK); one exhaust valve (probably from cyl 6). Shop said they set intake valve lash at .008” and exhaust valve lash at .010”.
Put engine back together with new head/intake/exhaust gaskets. Hand turned crank with new timing belt, watching belt-tooth position. With plugs out, crank and cams turned easily, with no obstructions. But, when I started engine, it ran rough immediately, with valve chatter on front head.
This time, warm engine compression test reveals:
- Cyl 1 - 183 psi
- Cyl 2 - 182 psi
- Cyl 3 - 181 psi
- Cyl 4 - 130 psi
- Cyl 5 - 0 psi
- Cyl 6 - 185 psi
Valve lash after compression test:
- Cyl 4 - Both intake valves at .011”; both exhaust valves at .010”
- Cyl 5 - Vtec intake valve at .008”; primary intake valve lash too large to measure (bent valve); both exhaust valves at .011”.
- Cyl 6 - Vtec intake valve at .009”; primary intake valve at .024”; both exhaust valves at .025” - but compression is fine.
Plan to pull front head and replace any bent valves. I don't want to do this again, so I would like to understand the cause of these problems: low compression on cyl 4, bent valves on cyl 5, and large valve lash on cyl 6. Possible causes:
- Could be something with vtec system, since I removed/reinstalled pressure sensor and solenoid.
- I may have bent the cyl 5 intake valve when I set the front head. When I set the heads, the crank was at TDC, with cyl 1 and cyl 5 at the top of their stroke. Before I set the heads, I rotated the cams about 60* from TDC, so there wouldn’t be any fully open valves. But, the cyl 5 valves may not have been fully closed.
I would appreciate any advice.