Help With Dauntless Lifter Noise, Please?

I've read through about 10 years of threads but haven't found a match for my particular question(I think...)
I've recently completed a full restoration of a '68 Commando half cab. This included sending the engine and having it remanufactured with all new internals(Long block). When returned, I finished the assembly with new.... everything... Timing chain, gear, tensioners, cover... new oil pump, oil pickup, new fuel pump, new intake/carb, HEI distributor, plugs, wires...headers.... literally everything. The rebuilder-company specified Lucas 30W break in oil with Lucas additive for the first 500 miles.
I went through a pretty normal startup and break-in run, but discovered an intake leak, so had to remove and regasket/seal the intake manifold. Changed oil & filtere(WIX) to the same, just to be safe and to ensure no coolant in the oil...
I've now put ~60 miles on it in short 2-10 mile trips. I'm plagued with, what I believe to be, lifter noise on driver side - but only when the engine is at full temp and idling at ~700-800rpm.
Oil pressure at idle, hot engine is ~8-10psi - obvious ticking from Driver front side
Oil pressure at startup comes right up to ~40psi and rpm, cold, is ~1500-ish (ambient temp is 50-60F) - with no tick
Oil pressure, at ~2200 RPM, hot is 30-37psi - no detectable tick....
But when I pull up to a light after the engine is at full temp, there's obvious "ticking"... & oil pressure is 8-10psi.
As I accelerate and RPM gets above 1200-ish rpm, oil pressure comes up and ticking is gone(as far as I can tell)
I've changed oil pump springs and am running the stock one...
I'm unsure if I've got a damaged cam, clogged oil passage, new engine teething sounds....
Is my oil thinning at full temp (185F)?
I don't want to cause damage of course, but I've been wondering if the Lucas 30W Break-in oil is appropriate now...After reading the posts in this forum, I've pulled the valve cover and checked the rockers... there's no play.
I've checked the "pads" on the rockers... they're all present.
I've run the engine with the valve cover off... there's oiling... but I don't have oil "spitting" everywhere...
I don't see anything unusual between the rockers operation... but I'm not experienced.
This engine did not have a cam thrust cap & spring when disassembled and so I initially assembled it without...After much searching I found those parts, disassembled the front timing cover and installed them, and just double checked everything..., reassembled. New oil(Lucas 30W breakin+additive&new filter)
Test drives still show the same noise...
I've run out of knowledge and experience at this point... If I've missed something or you have any insights, I'd be very grateful

 

Assuming a Dauntless 225 V6. Its possible you have a defective lifter on the left bank. The ticking likely is from a lifter not staying fully pumped up at lower oil pressures.
The best way to determine which one is by running the hot at idle engine (with the tick present) and valve cover off. Push on each rocker, pushrod end, with a wood dowel (I use my thumb) and listen and feel for the sound to change. Switch to the valve stem end if no change is determined.
-Donny

 

Yes, I would expect quite a lot more pressure at idle with a fresh engine.
If 225, how likely that the oil pump clearance is wrong? This is a major issue with the AMC engines, which have a similar oil pump design.

 

I like to rule out the easy stuff, Make sure your OP gage working and is correct. If it is, then it almost has to be the pump. I've always preferred a HV pump to a HP pump. If the pump is OK, then I'm thinking lifter too. It seems to me that all things being equal though, all of the lifters would be pecking if you have low OP. This makes me suspect the gage and 1 bad lifter or even a bent push rod. I'd also inspect all the lifters, it's possible, though not likely, to have an oddball in the mix. Like I said, I like to prove all the easy stuff. Good luck.

 

Sometimes an exhaust leak can be mistaken for a lifter tick. It reponds to throttle differently though, going away as you close the throttle. A mechanic's stethescope may tell you more.

 

I had the same thought. True, that. Or a loose spark plug. A 3ft. piece of tubing in one ear could locate it if so.

But the patterns he described don't fit, IMHO.

 

This is a remanufactured Dauntless 225

 

Thank you... Now that the weather, here is moderating, I'll follow your suggestion... I definitely need to isolate the specific source as a priority

 

Good suggestion!. I used a local muffler shop to install the exhaust... They were busy that day and several guys worked on the vehicle... so I doubt there was a lot of ownership in the final product.... The engine, of course, gets louder with RPMs and I wonder if it's masking an exhaust tick at higher RPM(Like cold engine/fast idle and/or driving speeds)...
I also installed an electric fan during the build and that thing sounds like a jet engine when it comes on... making engine noises that much harder to work on
My old ears need that mechanics stethoscope...

 

I previously took the valve cover off and saw all pushrods rotating nicely, so I didn't consider a bent rod... On your suggestion, I substituted a known good OP gauge and got very similar readings, so I think oil pump or lifter are the prime suspects right now.... How common is a bad lifter right from remanufacture?

 

I changed OP relief springs to the orange one and got increased oil pressure at cold (45-60) and somewhat higher at idle (12-15). Noise was less evident, maybe... but similar symptoms... The weather is supposed to improve this weekend so, I'll dig deeper this weekend

 

Bottom line
You have a pressure problem. I wouldn't worry about the lifter (unless if fell out) till you fix this.
Low pressure is caused by either too much clearances internally (leakage) or a malfunctioning pump/bypass.
Dauntless engines are prone to bypass valves sticking in the bore allowing pressure to bleed off. This is an easy fix, as the pump is external.
Gear clearances or pump damage (it's aluminum) can be the cause as well.
Otherwise, you are probably looking at excessive clearances at the cam, main, or rod bearings, or a galley plug is missing.

Personally, I would be on the phone with the builder before you crack anything open as the engine should be under warranty.

 

It sounds like you’ve done an incredible job restoring your ‘68 Commando, and you’ve really covered all the bases with a thorough rebuild. Based on your description of the lifter noise and oil pressure issues, here are a few things that might help troubleshoot and pinpoint the cause. I have this info online. I hope it will help you

• Switch to a slightly higher viscosity oil after break-in (10W-30 or 10W-40).

• Double-check oil passages for any blockages or restrictions. That was mentioned in the previous comment:

• Check lifters for proper operation, and give them more time to break in.

• Monitor oil pressure and lifter noise over the next few hundred miles to see if it improve

 

You can use a high-volume oil pump; they help with lower speed oil pressure issues without over pressure at higher RPMs. You can also use a 10w-/30-40 oil. I know a few that run a 20-50 oil.

 

This

 

I went back and read the first post, and have to question “new oil pump”. This usually consists of a pair of gears, with one driven by the distributor. Did you set up the clearances for the oil pump, or just drop the gears in and assemble? The oil pump MUST have the end clearance checked and shimmed to spec. There are usually a set of various thickness paper gaskets for setting it up. The timing cover (gear housing) also needs to be checked for scoring or excess clearance. If there is excess clearance, the pump won’t function as intended. Yes, you can put a set of V8 gears (with a spacer) for more volume, but the pump still needs to be setup to spec (blue-printed) to function as it was designed. A high volume pump is an acceptable band-aide for an engine with a lot of miles, but shouldn’t be needed on a fresh engine (unless you’re idling down under 500 rpm). Low oil pressure is likely the cause of your lifter noise, provided you don’t have a defective lifter. The relief valve sets the “high” oil pressure, typically around 60-65 psi. Low oil pressure is a function of engine temperature and engine rpm, provided the other engine clearances are in spec. Most engines I have built have 15-20 psi hot at 800-900 idle
-Donny

 

All:
Thank you so much for all the suggestions and thoughts… an update:
Checked plugs, all tight
Checked exhaust no sounds there
Changed oil to 20W50 added zinc additives(Lucas)
Verified 2 ways- oil pressure cold start, fast idle 55-60
Engine at full temp, having driven 20-30 minutes…
Idle at 660rpm. Pressure ~12-15
The lifter noise quieted way down…. Basically… it’s only noticeable at low idle, in gear, fully hot… 75% better ?
Question: I apologize for ignorance here but someone mentioned lifters breaking in over the first few hundred miles… I wasn’t aware… is that a common occurrence?
I used an engine stethoscope … on the valve cover.. then on the heads above each cylinder… there’s very little variance in sound at idle… maybe cylinder 1 is a little louder…
BUT… put the stethoscope on the top of the distributor cap and that’s the most obvious ticking…. Loud and clear
It’s a brand new HEI so it’s not worn…
I’m speculating the sound is picked up by the gear from the camshaft maybe.. but maybe I should swap distributors(I have another) to see if there’s a difference…
And maybe I drive it a few hundred miles and see?

 

In your first post, you mention “normal start up and break-in run”. What did this consist of ?
Breaking in a new engine is critical, especially for the new camshaft and lifters. A break-in run consists of running the new engine at 1800- 2200 rpm for 20-30 minutes to allow the cam and lifters to wear in to each other, with plenty of oil “splash” to keep everything bathed in oil.
Get the timing/distributor dialed in, and any major carb adjustments made in the first couple minutes. Watch oil pressure and water temps the whole time to make sure they stay in the normal operating range. After about 10-15 minutes, vary rpm up to 2500 for a couple minutes to see changes in temp and pressure, if any. Drop rpm back down to 1800 for a minute, then up to 2200 for another minute, and continue for 5-6 more cycles. After a minimum of 20 minutes at high+ idle, bring it down to around 1200 rpm and shut it down. Let it cool, then change oil and filter. I like to open up the filter to check for swarf after cam break-in.
Add a good high zinc oil, and the next start up, drive the vehicle on the road, keeping rpm under 3500-3800 for the first 25-30 miles. Vary the rpm, and the “load” on the engine. This is when the rings really start to seat. Drive easy on the engine for the next 150-200 miles, then slowly transition to more normal driving, but keeping your eye on oil pressures and water temps.
If the initial start-up didn’t include the 20-30 minute break-in run, the cam/lifters have a high likelihood of failing early in its life.
-Donny

 

Thanks for that !
Yes, that was the basic breakin process that was followed. I think the best course of action for now is to put 1-200 miles additional on the engine and see how things go