Low Mileage Persistent Lifter Tick Since Built

Robert Kenney

Robert Kenney

Super Moderator
Thought this might be helpful for others dealing with lifter tick on newly rebuilt or low mileage IH SV's or 4 cylinder engines.
A little of the back story might help.
I rebuilt the 152 in 2006-7. All new wear parts including a new oil pump (not rebuilt), lifters pistons, bearings ETC. After first start up and run, I realized that I had failed to install the front lifter gallery plug after trying to diagnose lifters that were not pumping up. Removed the front cover and installed the plug. Yes the lifters ultimately pumped up quickly, but one would still sometimes tick at idle. After breaking it in and a drive to Mammoth, it still had the tick. I replaces all of the lifters with new Johnston's and + .025 longer pushrods. It was slightly better so I let it go.

Fast forward to 2024,I'm debating selling the Scout because I just don't use it enough. I don't want to sell or try to sell it with the ticking lifter which has become a bit worse. Regardless of selling or not, I pulled the engine to find the issue.
I suppose this could end 2 ways, I fix the issue on the existing engine and sell the Scout, or I finish the 3-3/4" stroker / turbo charging project or something like that.

Stay tuned. I'll post the process and what I find and correct.

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Investigation results.
Cam and lifters look great. All lifters rotating as they should.

The rear cam bearing placement is likely the cause of lifter ticking at idle. To far to the rear and clocked poorly. Likely a 30%+ reduction in oil supply flow to the lifter gallery supply. The rear ward placement also impacted the bearing area available resulting in bearing subsidence which can be seen in the photos.

The valve / rocker arm supply was largely restricted also due to cam bearing placement.

While I did not install these cam bearings, I am 100% responsible for the flaws. This was 18+ years ago and my first IH.

I will install new cam bearings and put her back together.

A point I wanted to make on the various cam bearings available for these engines. The Engine tech bearings seem to have a harder wear layer, close to aluminum than traditional babbitt that Durabond uses. I chose the Engine tech bearing for this.


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Got the old bearings out and placed the new rear bearing. Lines up well and set flush with the front edge of the block bearing bore.
Should be able to get the last 4 in place tomorrow evening. For sure with the crank in place things are difficult to see.
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All bearings installed well, front cover, crank hub, and pan installed. Later today, valve train, and valve cover go in and on to complete the revisit.
These are very sensitive to the rear cam bearing position. I attached a few photos of the measurement to take care of getting right no matter who is building up your SV or 1/2 SV. Both clocking and depth locations are critical.
 

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Hello Mr. Kenney, I am the third mechanic to try to figure out why a sv 304 returned from having the engine rebuilt has crazy top end rocker noise.
When I initially checked the top end oiling, I thought everything was good as the boats filled up almost immediately at idle. However, upon further investigation, I noticed that the lifters were not pumping up. they were rotating but not pressurizing. I pulled the front cover to look for the gallery plug you mentioned in your post. Where exactly is this plug located? Behind the timing gear? Thanks in advance for any information.
Michael Whittington
 
Yes they are behind the cam gear. Should be able to inspect them through the gear opening’s.
Otherwise suspect rear cam beating is positioned wrong.
 
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