I have a Bosch solid state regulator and have been noticing low and erratic charge rates lately. Swapped it for a nos Bosch mechanical reg that I had in my stash. Charge rate is 13.8-14v now, perfect but, the mechanical regulator gets pretty warm after running for awhile. I measured the case at 130F. Is this normal for a mechanical regulator?

I would like to get a solid state replacement but the Bosch regs cost almost $400. What gives? did they stop making them?

What is the currently recommended replacement?

check with Mark...he has had new solid state and mechanical

@914Sixer

I have the hella solid state. Has been flawless and inexpensive.

I have two NOS solid state Bosch left. I can do $124 shipped for one. Agree that the prices are stupid for these. You might check your relay board, may be corroded under tar causing relay to heat up.

Am using a BERU solid state,

inexpensive and works fine. may have to modify mounting holes.

@Brian_Fuerbach

I still have a couple of NOS Bosch for sale:

http://www.914world.com/bbs2/index.php?sho...=359337&hl=

$65 shipped

Hella didn’t work on my car at all. I’m surprised to hear of someone that was able to use it actually

undo the relay board and turn it over,if it's getting that hot the tar underneath may be melting,check all the large diameter positive wires for insulation heat damage also.
Firstly check your heatgun ?.

I will pm you on the solid state reg. The ST reg I removed does NOT get hot, it just charges low at 13.2v max unloaded.

The mechanical reg I replaced it with is new and was purchased a few years ago from a world member but never used. This mech reg gets hot but charge rates are correct.

So a mechanical reg is not to supposed to get hot?

I looked at the bottom of the relay board and and it looks really good but the original solid state reg did not get hot. The mechanical replacement is getting hot. I measured the 130F with a Ratech IR non contact thermometer that has been recently checked against some known values so I believe it is correct. The reg seems to top out at 130 which was confirmed every time over a couple of drives. I have read on the google that “mechanical” regs act as heat sinks in their process of regulation.

Anyone have a “Bosch mechanical” reg that can confirm running temp? At least touch.

Van; yes, a few of the standard electrical replacement parts don’t work in some of our 1.8s yet do work in others’. Alternate flasher relays and Petronix just don’t work in mine. We’re special….

Wondering if anyone has had this problem before. Car is a '74 2.0. Replaced voltage regulator with a new Hella unit. At 1000 rpm idle, voltage measured at the battery terminals was initially steady at 14.5 volts (too high), and now is fluctuating from 12.5 to 16.5 volts. Is that likely a bad regulator or could a problem elsewhere in the charging system produce that fluctuation?

@StarBear the Petronix works beautifully in my car. I can literally see the difference on the timing mark; rock steady.

But my experience with the budget Hella unit was exactly as @Lockwodo described. I now have two Bosch solid state units. The old style solid state delivers 14.29v consistently per my cheap multimeter. The new style gives 14.00v constantly. The only caveat I have is that both require a little throttle bump to get the voltage light to extinguish if you have a sluggish start in real cold weather.

Forgot the brand, but I found an adjustable VR
Been in the car 10+ years
I’ll pull it and get a pic when I return home

had issues with the Hella repop from Pelican ,with my newly reconed Bosch altenator ,bought a NOS Bosch one of Mark an all is fine.seem to remember they need to me matched by the sticker in the 911 enginebay.

I purchased a mechanical Bosch regulator from Brian and tweaked it to put out just over 14 volts. You need a loose .012 between the contact points.

What temperature does it get up to. Hot to the touch or cool?

Why would this increase the output voltage?

This is what I used. Less than $30 from Autozone. Worked for the last 2 years, but only ~1500 miles.

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Went to a site specializing in old Volvos. The stock regulators seemed to crap out when I would turn on the lights or anything equally reckless.

See: https://www.ipdusa.com/products/6781/Adjust...t-IB301A-105443

This the one I’ve used for 15 years….

Probably a dumb question, but you're using this on a Volvo, right? The website didn't show an option for 914. Another question, how do you adjust it? Is there some sort of adjustment screw and do you have to pull the VR out to adjust it?

Hmm, so the voltage regulator saga continues.

After the mechanical Bosch VR on my 914 crapped out, I bought a Hella VR and installed it. Voltage at the battery was 12.6 volts (ignition off) and 14-17 volts (1000 rpm idle). So the voltage at idle was way high and fluctuating. The vendor agreed to send a replacement Hella VR.

Installed the second Hella VR and voltage at the battery was 12.6 volts (ignition off) and 14.8 volts (1000 rpm idle) with minimal fluctuation.

Two questions for you guys:

1) is anything over 13.6 volts at 1000 rpm idle too high? I've seen at least one website indicating that voltage over 13.6 volts at idle could cause electrical component failures.

2) at 1000 rpm idle, how much voltage fluctuation is OK? With the first Hella VR and all the fluctuation it caused, it engine seemed to run unevenly over 1000 rpm.

Thanks!

It on the 914

Hi all. I wasn't getting any joy from the two Hella voltage regulators I tried (see post in string above), so I decided to buy one of the adjustable VRs mentioned by Jim Hoyland. I bought this one on Amazon (manufacturer and OEM # IB301A) for $35:

https://www.amazon.com/dp/B014GN1YLK?psc=1&...product_details

Out of the box, the charge rate was 14.1 volts at idle. I turned the adjustment screw counter clockwise to set the charge rate at 13.7 volts. I will have to modify the bracket on the VR because the holes don't line up with the relay board mounting holes (same issue as with the Hella VR). Liking it so far!

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