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Old 11-08-2018, 06:19 PM
Trent and his Rover Trent and his Rover is offline
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As some may have read, the head came back from the shop with its valve springs upside down. After repairing and installing she continues to "miss." Compression values are: 145, 90, 115, 120, 140, 130, 130, & 125. Wet testing the 90 value jumped to 110. Gonna install new rings at the 90, 115, & 120 pistons. Thought I'd post this to see if any other info came from the forum. Thanks.
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Old 11-08-2018, 06:56 PM
Swedjen2 Swedjen2 is offline
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Do them all and get it over with. I've NEVER heard of anyone doing a ring job and not doing all cylinders, unless your in the middle of the Sudan, surrounded by al-Shabaab, 300 miles from the nearest station and you only have 3 sets of piston rings. Don't chinse out.
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Old 11-12-2018, 02:20 PM
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ptschram ptschram is offline
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Upside down valve springs? Curious, I didn't know they had a "This side up" mark.

If you are doing rings, you'll be doing rod bearings as well as I can just about guarantee you that you won't have much oil pressure after disassembling and reassembling.

Miles on the engine? When you did the headjob, did you inspect the camshaft?

It makes little to no sense to strip the heads back off (they will likely need resurfacing again as they may well have warped enough during the little run-time it has on it after the headjob) and remove the rod/piston assembly without also replacing everything that wasn't replaced during the headjob.

My suggestion, keep driving it.
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Dominic Perodeau and John Monaghan are thieves.

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Old 11-12-2018, 03:21 PM
p m p m is offline
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Originally Posted by ptschram View Post
If you are doing rings, you'll be doing rod bearings as well as I can just about guarantee you that you won't have much oil pressure after disassembling and reassembling.
I wonder why's that.
I replaced the rod bearings with stock-sized new ones and haven't had any issues with oil pressure.
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Old 11-12-2018, 03:35 PM
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ptschram ptschram is offline
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I wonder why's that.
I replaced the rod bearings with stock-sized new ones and haven't had any issues with oil pressure.
I have probably sold 10-15 sets of standard sized rod bearings to folks who have called me back shortly thereafter for oversize bearings.

The main journals don't seem to wear that badly, but the rods are almost always at least 0.015" under.
I just expect to have the rods and mains ground 0.020" under as a matter of course

The one time I put a set of standard bearings on a worn crank, it lasted a few hours
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Dominic Perodeau and John Monaghan are thieves.

I'm still in the parts and engine building business-my service activities are being reduced, not my interest in serving the Rover community

I am easily contacted via text message to 260-804-0458 or pt@ptschram.com. PMs are least reliable
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Old 11-12-2018, 05:13 PM
p m p m is offline
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When I tore apart the bottom end on my D1 with 250k mi, all rod journals were less than 0.01" under - so I put back stock-size shells. 35kmi later, the engine is whisper-quiet.
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Old 11-12-2018, 05:43 PM
Jeff Blake Jeff Blake is offline
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Typically you're only fitting oversized bearings if you had to get the crank turned due to a nick or gouge. For mine, I just had the crank polished and used STD bearings.

Easy enough to put a micrometer on the crank journals and decide for yourself before ordering bearings

You're compression numbers are low all around. Should be 180. I would also bore gage the cylinders, measure the pistons, and compare against data in the overhaul manual. Just putting in new rings is a kind of shot in the dark and a lot of work to be guessing on.

IMO either keep driving it or do a proper engine rebuild
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