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Bore scope Exhaust Valves

JohnInReno

Well Known Member
I welcome comments or suggestions on these 4 exhaust valves. The engine is a Superior IO-320 with roller tappets, dual Pmags, and 400 hours since new.

Please pay special attention to #3 which is exhibiting erratic EGT at idle only. Possible sticky valve? Cylinder #2 also has a half moon mark on the edge that I can't explain.

Obviously, I am new at this.

Cylinder #1
7DGRDGgn6jIKIKv42r0qb0AtbJoD7u7atQxFepGIUZzRDJP0KmIt8SQnd4qCCYUCw6_XHp3EYs0oDMmFYXHKCTgArbUQ3XTXumGbBKU70M6AfIqWk5-A4WAB29TriNwRBFusI9_2dj-7f5zwrnTK5kFWfThS2Y486NO0__9yuQZ_2ZseVifAo5nKT83qz2GPNcZeLddywS9o5Y8m4aR1oWhVsslju8X08GTdYQJYK7946wawheJCdSEmuxP8S96Pd4SnsV85piuNc9fYdRPIsZPzGW2uuUoSH02rnwQD1Rj6YnApcc7CLur-RTxdB6CleEJnIOQBEqiHjxQVpag6iaR2V4N6Vb3ObHFdauSUCoLGbY33ojav7s5MC4nkZ5TwWfJjVH_xhj1xQwuiGGcb46Jj9zkTvJ4wknPEvSfkxW9g4v4pJt-FcvXV95NU0bgI_uqwYn6f6TiTIYkohtrU7Ay8Jua_riW6nEW3qp6r610Ca3WO1Rz3z-jV3513UkzwV0cB2OpkT5IALAVVvDc9P7ZusChjZ2f0e5SCAd2xgqwaCRf2TZbwUa_AxI-3cnyKj7lf_jXzJkPidnkiD0FYERoo4eHJPvAdjkikw93VwgogQKB4pdFoEKcV2Uob-oUlnmJs5EJ0y--HRAMG8wpPf6PqQA315kVtJzVE2JY0HQ=w500


Cylinder #2:
1trS4Myjtjm0LsWNzhP84OHJzUKnxguYLjRcsFqyx-kDxP6S3iWq6WLp_fdB-g4gSChqaIsMbjcBuDy3FtPL_jYnZYQJL6d_U_Aba4Q7r0xrtivZ_HvPgyPd_dIyjJHs3SmMK5N6n7BvARXzri8ZgQLYhbkFE-fKgX5op4pHDkceTPCZwXYEMIjwXURqDYtSEq0AbjCr6WEaTrb1Y8Bwmi8NamCPWHG0pmp4rr-6Ch-T9mqMOtodWT6UlyO3JOA7veLJDHcScFyXcLmR3fV-HzBif2xoo0nfpGJcLn82E_vfJNwrsGjF62aEbwxdbhi4f6fgXlJzBQ6wGIK79vCKyO-qFGyY_r6JJuceqtYms83_KYYw6rtQWmukRmDU5eVv3kV2ZvKj7yOsA8MP0mFEOiLtr55wZR8t9zw8j3o-eZkmbHC1P_g_8v4mJsiu18nGC_jBLgAViSIVEU7NFsDtpPk05zWQLL_jJJ_2C4Nvo6U4gWhbWjfAPy41y1IuCXoadR-HVMKssHMhTsWycYakXDcIhz5wkZswmMBEwFNsWGi6MGr77rLa9pRWfP6xdlbWOqwJSbFaaEE1CgYAlIMl043NvUBbIS0WbdOkf8RXbEi2-x2L1LZH_IprTGv39VajP-OkkibF2S3bHp8uAcLvjwXe7ermwv6erY4DDqqQVA=w500


Cylinder #3
AC3EXpeVjM-_jmxflG11YJlepfISNdcTqenv9MCR64sAG15rpnK76MutgxqHbckYMjunXIx5Ufx07FcvjX2W8xZkQDPxZHmykIPSuEETd17zZGd8Ni_q0SR_1LmSvZQX3dV-GiuC1Z9fC9VL8a_4hF4szbF7EgQIB3hBxfT8aSDvvC2eL2DJLFJXzFappQ6ycFj667Bs3x0MqFgaasQAVK2-VPRhcakH8UZLdMDdo60qPLIslD-ztE7fSVaNMKG2XxxOHyUp4LMVoKwwH1e2BdZEk6TfenERBZgt-_nZWAZG7-Al4nVIPqTfRenm7iFqrl2l_dPIUV5a3ecF-57FsMyEt5bxIJgklKBLPuHJVCpKt9LZpwu1u-DeLwvGhgSbDdb87GyfWO14VDROtYAdP1vHI9WjGue4aRWXRv_gaBO_ZQO2vhKL6bJu0lFGbpfw9azu062d7qs1BAdn7N0DWcQOel-XZ3pF9EKXuTNVygcHqME4kIno2C7YVUSMfYLtfNk7FaxzWj1uqN_6-snncL7HJgjIliBnJ3Byj9LS1iltUaUQscOvqGpeHvK8MEZm_frfM459JCelqbW3N1-JHWn6k9fz-7ZCKL08cHORm-KBOYl_jm3bUUl_9LXIjLECEZR6MLRFNKpXfXo8zGR8dHn1pN1g81d_MCXAFmRZ5g=w500


Cylinder #4
MPmI06mHJzfzliLULtd3aTcJ0T_K-4k5DVynHF0hqkx0PlbvSddPkD-365i15ovb5_LcdKyMUzbtPGKE3N_DVkAI0djTLhljfR5CgHtdjAqTVH6lM-wCPLCKERslVCYeUsPkgtbAW7t0pWYH8uzC7OezU5txo4A7n4TQ8jm8y1_hjO4E3tg14-2a3MQtLHZaNRG1dfVNA9gNfDfXO9_F7vfayCA2xK5b-6Gs73vN3qO7SJWPKO3XZkEqu34d727gxIJHGqIRdDnr3Mb64Qhb9-AuOldeGaiiNDc6_ep167cZtGbLBbJae5hGlGEYYTKKaS8IAHiGc52VCU1WYwe1W9WWetXghK2fjru1Z-sLc4rmFb7wNcVcqnHIj-HAvyG_rSrdhqzacwAjsmUaH_HjDeU5E2nj0wlmmVL2CtZ51NAQbAqKFpkIGsVjsDlz_deyfd5PpjcTvqPRahFsK8oru1O_9CDGEuCNvACY9IOabF6PQf7iz8m0aYmtjpxPPUAJwA1wXMcb1IU3JF4nTROj4sQLywGIXeRj0jfIf9nADYCGzSO8zSwJrlK7x9gQ8zOUUfySxzxSfYAeCUBDnCWqCNsn7EkVLExeiletxWbTExRPuC485dVII80kal5Cs0YbV0oe47OM_gLrxPXTDxOnwqFmue0kZUgcIrP5t2Mrww=w500
 
The edges on #2 and #3 look suspicious. You might get a picture with the valves open and get a look at the seating band. A leak down test listening at the exhaust pipe is another diagnostic to be done. All together maybe a picture emerges.
 
They look good to me. 400 hrs is time for a valve wobble test. That is the only way you would find a sticking valve.
What do you mean by erratic EGT at idle?
 
Savvy Analysis

Engine monitor with download capability?

You might consider signing up for their pay service, they have an analytics program called "failing exhaust valve analysis" or FEVA that has a very good probability of predicting whether you have a problem.

Their website has more info on the subject.

https://savvyanalysis.com/content/feva/
 
More pictures

The edges on #2 and #3 look suspicious. You might get a picture with the valves open and get a look at the seating band. A leak down test listening at the exhaust pipe is another diagnostic to be done. All together maybe a picture emerges.

I will try to get pictures with the valve open. A leak down test is also on the list.

Thanks,
john
 
You can also watch the valve open and close, I've spotted a worn guide doing that. You can see the valve slip sideways just as it closes. Obviously, don't squish your gadget with the piston.
Tim Andres
 
That pattern at 11 o'clock on #2 would have me looking in there often.
 
#2

That pattern at 11 o'clock on #2 would have me looking in there often.

I got some pictures with the valve open:

Cylinder #2
90Rfci6U4xKkVNyolYPXdRSgpPZyiFkp_lgSixmyif_F4-SKrsgQ_NCdgDAvrnkd_i6Pp3ykURBolJUM78gjzzlTW7ALQUxNvXWesYjkCMaZuWArIYeF7ux-PZALSjCGNOGJRG3erYbPc_NvQ36uuHLkW3Na3fvEvno4RaG6ToHpbOBqRc5bokR-ry9vEPdUoRKbENc8bAXinYBYNPeuvcJ3uj5-gWZAlkLwoNyx46rHbyFjiTzirZChDooVbwV9irXKq2lOoXGBmCQwDdkfd0qRIGvUkX7hQgFCJwPEWEbmUjnvpgq9bySNhmpwEacmosh2ykiFu7sR3TMfrNizjgzEg88SL0RV_hcpjqtX4IeZEY6iZesxoTKvMGNJpCjznbE6WdxrEt-mOc0ACBPlzcEh208dZ6kKdgJfkV82k1RTgyqYIMvTFWT0mL1ajY42aMcnM8hqAGGcP8aCoBoUkjIWueynWW0wPU92ga6NBRtyZrGWUGJYal9JbG0D8oFVsjJJArnz4vnQfGTyj4JeLgJBzThXnJXWdjMz8Ri6tS-FXz5uNUBsK6jOhj4C-bl9bZdLi095i7YRf4a7svFe-XCCgs2E-MCijQqtcdP5IoAREsvGZi0h=w500


qGSSLGruK8wt3m0kYN-3KB4UMQOn1UhdaH4puQss3GNXwuVlqmkbZgd6pd21PnaRHnkyJC7o_0xkOifV551hAQH_91EAHJuvDCy9G5uR2NWn052yGmEG2DIdFq1jvRKwVeDqCDytppaN3x-oU0wxlDdld-9ySG9llJ9UdPVnilA5ldPGG4gi8GQZyCHga2tciXmjeJIE9b0ZgMszChKIdHJbS3qmiqcPgTfMWAQWb2pZ1t2gM-IoVpHdzg-pBe7VwUjbqX_gOKHuvkgBsru2wRceWbsIddUhnVmCN1m2WycmKIpURHcMBS0C7R5LeDfVpG-CKNKDCA87Toeuh5K8Vyb0ryQ2aCWYESOszaQPJ1ff6sS2fJJE6vezJToFcNbyB_8tSZMS6Aw0j1TRUEHTl3Qd4N6-7Mgdsoxrf20RjLfvnu0_3xxNvDmSH1VTUV4TqiDKVH2sz_7mVGULdcI_WDCEY6POvjJlnVgX2RYEyWw-eyBSjs6ZXF9yGLp6W32W9jlzEBGUkv6HAfSumNWNE_6eSAC3JST7juDG-1rchB7DYRYsKdOUzcnXkiH6LpF0hlK0lc5WKyqFg4mqtPyQfQ3ZjBAQm180QiV0DOFlqoGPJChI=w500


Cylinder #3
LNBOerWAmofWo3cbeMTharItP87yS--jbLY6004wVwfIim_RYXfEOX5H6YUhiaPdt7i3rtszwJ-HjIqBFXamosDUNOKhlyAJy8nHqFOSSS91SFxqsv5xs69bpI3kYhiWA2Wk8Cbt_QrQP6iedZ8SSyBNKvbz_ktt8LFldpJtGcFA-EiJPwHxGBksFjVU5BBI2b5thUQMXtEPqKylUvnjAlkqP-uQHSqhJh6P5rycMEBtr9xBuxeukmCD9JFP87UsR9s_5tHXtigwuBfM78DhVciEppfZcHwMab0n0GB1X-_mj42YVSBV1sTp4tUzEQcpGN606VTU4u6Obqi-8MxI8bLC97GruE6OJnWyDrkVm94imj9K3Grdyiv09ntaKmQ2XmTUvm-BsBXcg4QYH5RyFCUqekTxNpuXhsXiQidBBOEENbykekxvq_LHXcfDKcRbQhm3_miDzINPVefoOLzCO5sI-fEX5gC-GPJi5qRowqCbbOU_gW_gnVfs9fbv-EKzUOP3QMTo1l2FZQ9wLqQk1-BgCQCNkxtTQ3W2NtHMd4-uV1vk3OWhMjit267pC4c5sJe2HyiUEaEcgwEMF2Sf_7NEGzGWmjFqOxpcPQQx8yxHo3f3=w500


Can someone tell me if the link to SavvyAnalysis works? It works for me but I am not sure about others.
john
 
One more of #3

If I am seeing the ring where the valve seals against the seat, then the top of this picture looks odd:

Cylinder #3
VWCSmNbTMWo_c4uBpxGJF8rULhcMJKLDASeXgF1Pa18PUXWaEb5_xquFg9jFOGya8Wd5vdVJa7wWbEUQ7iBrvS1yH_aHwy5p_zNFpkX05Vekh1sNjqiT6WYsLM9lwYJaSsTnnyF-6FpWw9Qc9no2pGdfEjLKCro7OM4oJDP8t0nlEVObRS1PyqUqushRZpsU4zXiNiHLuaYojHWDLPE-HV32BY0uMHgoybRa87FxdjeBWmDlOJmS4Vo7C_LLKHAX7Hx2hEmnQ43W_HTxpNTS3keULaiNTrIMZ9oB7cHvCVtxjEiXhi5un70Psow5pz15SGdgVGq7y5fXXtDcHte9m2d8_TKPoZ-rY3zkHZcZUadGSr3HiLrSK6uQVih0F00kEES9XiBv5Wcr1Vf75PYkAzpsptJ3IYQ1icMGh4M5Rj7_iw0UYVvtJZRvLezP5modStxairavHDAQ4D7mZin7lfts0iE3VGo-xTUIARGYyQ9YTCB3-J5-Ksd8oEaGRAW7nFgudy_SgDDwzJgFJTDX27HOX81CIgD21Th-twHPv950HUJjtibX7X7SOsR-39ePd0ShcN0adPPLx5jbyV2EA9O3InhmJ8lXgf5EVT5JKVXpIvTW=w500
 
looks like some build-up on the valve seat. I would do a leak-down and the wobble test. Then run it hard for a few hours and look again.
Do you have anything that can reach in and scrape the build-up off?
Are you running this engine ROP or LOP ? It looks like ROP based on your fuel flow of 10.8+gph (your link works). You have an IO - take advantage of it and research LOP operations.
Everything looks fine to me. See what others say.
 
Odd -the new images are a big negative sign for me, meaning I can not see them. The OP is fine though.

_yes the Savvy analysis link works. If it was a carb one might consider a leaking intake tube. You could have a restricted nozzle, though, or a sticky valve, or a leaky valve.
 
Last edited:
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