B7100 blow-by question

AOW162435

Active member

Equipment
B7100
Jun 16, 2023
102
51
28
Ellicott City, MD
Hello again. Last year I posted about the new-to-me '79 B7100 I purchased (B7100).
Following a thorough going-through & servicing, I took it out to our property in WV and put to work pulling a 5' mower every few weeks. At the time, the tractor had 928 hours on the clock.
The tractor starts correctly, runs fantastic, has plenty of power, and generally does what I need it to do. When I first purchased it and ran it, the blow-by from the valve cover vent tube was minimal at best (completely normal from my experience). A few weeks ago, I suddenly noticed a much greater amount once bringing it to idle. It will rev up butter smooth and run at full RPM without an issue, but once dropped to idle, the blow-by will immediately start.

I have read many, many posts & write ups online, both from here as well as on other forums. The end result is that I'm no closer to figuring out if this is truly problematic, or more of a nuisance. I did read that the breather has a screen that can become clogged - I'm happy to remove the valve cover and do so.

But based on my write-up, can anyone offer a fresh perspective on the matter? At this point, the tractor has around 950 hours.


Andreas
 

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TheOldHokie

Well-known member
Lifetime Member

Equipment
L3901/LA525, B7200DT/B1630, G2160/RCK60, G2460/RCK60
Apr 6, 2021
8,303
4,185
113
Myersville, MD
windyridgefarm.us
Hello again. Last year I posted about the new-to-me '79 B7100 I purchased (B7100).
Following a thorough going-through & servicing, I took it out to our property in WV and put to work pulling a 5' mower every few weeks. At the time, the tractor had 928 hours on the clock.
The tractor starts correctly, runs fantastic, has plenty of power, and generally does what I need it to do. When I first purchased it and ran it, the blow-by from the valve cover vent tube was minimal at best (completely normal from my experience). A few weeks ago, I suddenly noticed a much greater amount once bringing it to idle. It will rev up butter smooth and run at full RPM without an issue, but once dropped to idle, the blow-by will immediately start.

I have read many, many posts & write ups online, both from here as well as on other forums. The end result is that I'm no closer to figuring out if this is truly problematic, or more of a nuisance. I did read that the breather has a screen that can become clogged - I'm happy to remove the valve cover and do so.

But based on my write-up, can anyone offer a fresh perspective on the matter? At this point, the tractor has around 950 hours.


Andreas
Fix it till you break it 🙄

Dan